Heartbeat Bullet

Heartbeat Bullet
TitleHeartbeat Bullet
DeveloperDear My 1bit
Publishers Dear My 1bit
Related anime[DB-ANN] Katekyou Hitman Reborn! (2006)


Heartbeat Bullet is an unofficial doujin dating sim based on the Katekyo Hitman Reborn shounen anime/manga series.

Main characters

Dino O
Aliasesディーノ, Bucking Horse Dino, Chiavarone Decimo
MeasurementsHeight: 183cm, Weight: 72kg
Birthday4 February
Hair, Blond, Short, Spiky Bangs
Eyes, Brown, Hosome
Body, Pale, Slim, Tall, Tattoo, Young-adult
Clothes, Belt, Hoodie, Sports Shoes, Trousers, T-shirt
Items, Whip
Personality, Clumsy, Friendly, Kind, Mature, Proactive, Protective
Role, Gang Leader, Italian, Mafia, Pet Owner
Engages in, Fighting


Dīno is the 22-year-old 10th Boss of the Chiavarone Famiglia, which is the number three Famiglia in its Mafia alliance with the Vongola Famiglia. The Chiavarone is also one of the largest Famiglia, with over 5,000 members. Dino is a young man with great leadership skills along with great combat skills. His main weapons are a bullwhip and his pet turtle, Enzo.

Like Tsunayoshi, Dino, at first did not want anything to do with the Mafia and was also a klutz. He became a suitable Mafia Boss after Reborn became his home tutor. He came to be known as "Bucking Horse Dino" and fixed the Chiavarone's financial problems, turning them into the third most influential Famiglia in the Vongola Alliance. Unfortunately, Dino is so devoted to his Famiglia that when none of his Famiglia Members are around, his skills decrease dramatically, and he will often accidentally hit people with his whip and fall down stairs, among other things.

He refers to Tsunayoshi as his "little brother", and treats him as such. He is also one of the characters who refers to Nana Sawada (Tsunayoshi's mother) as "Mama".

[Taken from Reborn! Wiki.]

Gokudera Hayato
Gokudera Hayato獄寺 隼人 B
MeasurementsHeight: 168cm, Weight: 54kg
Birthday9 September
Hair, Curtained, Grey, Short, Spiky Bangs
Eyes, Green
Clothes, Jacket, Necktie, School Uniform, Shirt, Suit, Trousers
Items, Grenade
Personality, Antisocial, Loyal, Rude, Short-tempered, Smart
Role, Classmate, Half-brother, Half-orphan, Italian, Mafia, Middle School Student, Transfer Student, Wealthy, Younger Brother
Engages in, Fighting, Smoking


Gokudera Hayato was born in Italy and is 3/4 Italian and 1/4 Japanese, having a half-Japanese mother. His all-consuming ambition is to succeed as Tsunayoshi's right-hand man. Hayato first arrived in Japan to test Tsunayoshi's worthiness for becoming the heir to the Vongola Famiglia. However when Tsunayoshi saved him from his wayward Dynamite, Hayato became fiercely loyal to Tsunayoshi; admiring him to the point of extremes.

Hayato is hot-tempered and tends to be irritable towards anyone who isn't Tsunayoshi or Reborn. He cultivates a "bad boy" image by smoking heavily, having a hostile attitude towards most people and dressing like a delinquent. However, over time, he gradually starts to open up to others. Hayato is rather superstitious and believes in "Unidentified Mysterious Animals."

Despite his rebellious image, Hayato excels in his schoolwork and aces all his tests, often tutoring his less-skilled friends such as Tsunayoshi and Takeshi. Gokudera also bases a lot of his thinking and academic prowess on mathematical theories that he develops. It is commonly assumed that he had a multitude of private tutors when he was young, as he was brought up in a rich household.

[Taken from Reborn! Wiki.]

Hibari Kyouya
Hibari Kyouya雲雀 恭弥 O
MeasurementsHeight: 169cm, Weight: 58kg
Birthday5 May
Hair, Black, Short, Spiky Bangs, Straight, V Bangs
Eyes, Grey, Hosome, Tsurime
Body, Average Height, Pale, Slim, Teen
Clothes, Jacket, Necktie, School Uniform, Shirt, Suit, Trousers
Items, Tonfa
Personality, Antisocial, Cold-hearted, Confident, Disciplinarian, Loyal, Nature Lover, Violent
Role, Delinquent, Discipline Committee Leader, Mafia, Middle School Student, Pet Owner, Senpai
Engages in, Fighting


Hibari Kyouya is the leader of the Namimori Middle School Disciplinary Committee, prefects who are in fact a group of delinquents that are all loyal to Hibari. Hibari himself is a violent delinquent who uses his status to harass other students. As shown several times in the series, he prefers to be alone and cares little for his subordinates. He loves Namimori more than anything, and will often say "I'll bite you to death," or "kamikorosu," to those that disturb Namimori Middle School. Hibari is very proud of his school and is apparently the only person who even likes their school's anthem, even using it as his ringtone. Reborn piqued Hibari's curiosity in the mafia early on in the series and Hibari considers him a worthy opponent, having a strong urge to fight him.

As stated by others, Hibari is a very scary character with no care for the well-being of others, preferring to do whatever it takes to get what he wants. This often leads to his opponents surprising him, as he doesn't think before attacking. As the head of Namimori Middle's Disciplinary Committee, Hibari uses authority to assault those that get on his nerves, including his own subordinates. He prefers to be alone, and hates crowdings. This leads him to beat anyone who he thinks is crowding around him too much. He has full confidence in his own strength and power, and dislikes working together with anybody due to feeling bound and restrained, making him refuse or not easily take suggestions from others into consideration.

A rare trait about him is his love for small animals, ranging from birds to hedgehogs. He is also fiercely loyal to his school and its rules, going so far as to punish others for breaking them even if they aren't students or at the school. He is shown to dislike being indebted to anyone and strives to pay them back as soon as possible. He cannot stand being restrained and absolutely refuses to allow himself to be controlled.

[Taken from Reborn! Wiki.]

Rokudou Mukuro
Rokudou Mukuro六道 骸 
MeasurementsHeight: 177cm, Weight: 62kg
Birthday9 June
Hair, Blue, Parted in Middle, Short, Spiky Bangs
Eyes, Blue, Heterochromia, Hosome, Red, Symbol
Body, Average Height, Pale, Slim, Teen
Clothes, Gloves, Jacket, Necklace, School Uniform, Suit, Trousers, T-shirt
Items, Trident
Personality, Arrogant, Blunt, Refined, Relaxed
Role, Gang Leader, Mafia, Middle School Student
Engages in, Escape From Confinement, Fighting
Subject of, Human Subject Research


Rokudou Mukuro is the Kokuyo Arc's primary villain. Portrayed as the series' first primary antagonist, Mukuro Rokudo is introduced as a 15-year-old (former) Mafia criminal and the leader of the Kokuyo Gang, which consists of heinous criminals who have recently escaped from an Italian prison.

Despite often being shown with a playful smile, Mukuro is seemingly apathetic to the suffering of others. Appearing as the series' first antagonist, Mukuro is not averse to disposing of those who get in his way and is not easily intimidated, usually speaking to others in a very direct and arrogant manner. He cares little for others, and simply considers people to be "toys" or "tools" he can sacrifice in order to get what he wants. Though usually calm, he is easily angered in some occasions, mostly whenever his hair is compared to a pineapple, in which case he would immediately give the offender a punishment, both ruthlessly and comically.

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Mukuro, along with Ken and Chikusa, has a great hatred for the entire Mafia underground, most likely due in part to the experimentations they suffered as children. However, not only does he have the desire to destroy the entire Mafia, he also wants to invoke world suffering by starting a world war, claiming to want to cleanse the world with darkness because he sees the current world as worthless.

However, later on in the series, he becomes Tsuna's Mist Guardian. He takes on a more supportive role for the series' main characters, becoming somewhat of an ally rather than an enemy, though he prefers to not consider himself as one of their allies and avoids any involvement with the Mafia due to his past.

In spite of claiming that people are just toys, he is considerate towards his subordinates, particularly both Ken and Chikusa, and possibly Chrome, protecting them and even sacrificing himself when it's necessary. However, he does not directly do so in front of them and never admits it openly, hiding what he truly feels about them from everybody.

[Taken from Reborn! Wiki.]

Sawada Tsunayoshi
Sawada Tsunayoshi沢田 綱吉 A
Aliases10th, 27, Dame Tsuna, Juudaime, No-Good Tsuna, Tsuna
MeasurementsHeight: 157cm, Weight: 46kg
Birthday14 October
Hair, Brown, Short, Spiky, V Bangs
Eyes, Brown
Body, Average Height, Pale, Slim, Teen
Clothes, Fingerless Gloves, Jacket, Necktie, School Uniform, Shirt, Suit, Trousers
Items, Bag
Personality, Clumsy, Coward, Flustered, Hetare, Low Self-esteem
Role, Classmate, Gang Leader, Kouhai, Mafia, Middle School Student, Unpopular
Engages in, Unarmed Fighting


Sawada Tsunayoshi is the main protagonist of Katekyou Hitman Reborn! Although at first a cowardly and useless junior high student, Tsunayoshi is suddenly thrown into fulfilling the role as the tenth generation Boss of the Vongola Famiglia, the most prominent Mafia Famiglia in the world, forcing him to gather his own Guardians to eventually battle for the survival of the world. Although he himself does not wish to have anything to do with the Mafia, he nevertheless finds himself thrust into numerous battles.

Tsunayoshi is an ordinary junior-high student known in school as "No-Good Tsuna" for his poor grades, wimpy attitude, bad luck, and lack of athleticism, a fact which he freely admits. Tsunayoshi is generally depicted as comically horrified by the outrageous actions of those around him, generally causing him to become nearly hysterical, especially by Reborn's training methods. His lack of confidence and tremendous lack of luck generally contrast humorously with the positions of leadership and external pressure Reborn puts him in. Despite his title, he seems an earnest individual with great potential; unfortunately, Reborn discovers that often the only way to force Tsuna to fulfill this potential is to put him in a life or death situation.

Although told by others that he is to be the 10th generation Vongola Boss, Tsunayoshi is generally unwilling to take part in anything that has to do with the Mafia. He always denies the fact that he is a going to be Mafia Boss and tries to avoid anyone and anything involved with the Mafia, clinging to any element of an ordinary life he can, even stating that his Guardians and subordinates are just his friends and upperclassmen. Later, though he dislikes the violent history inherent in the Mafia, stating that he would rather destroy the Vongola Famiglia than to accept such a heritage, Tsunayoshi is grateful for the friends he has made since meeting Reborn. He cares a lot for his Famiglia and puts himself in the way of danger and even death in order to protect the members.

[Taken from Reborn! Wiki.]