Jin Bubaigawara aka Twice

Jin Bubaigawara is a 31-year-old man, who had a rough life. Jin's parents were killed during a villain attack when he was in middle school; leaving him an orphan with no blood relatives to take him in, and having to focus on finding paid work. He ended up finding employment that gave him food, clothes and room and board. However, when Jin was sixteen, he accidentally ran over a young man with his motorcycle. While the victim survived, he had broken his arm in the accident. Despite obeying the speed limit and insisting to the authorities that the man jumped into the road without warning, Jin was given a criminal record due to the incident. When returning to work, he was punched by his boss after getting a complaint from a top client, who said that the victim was one of their workers and was furiously threatening to pull all their contracts with them. This resulted in Jin being fired, evicted and left homeless and alone.

Eventually, Jin's depression and loneliness became so severe that he used his own Quirk to create a copy of himself to comfort him and have someone he could trust and talk to all the time. He later created more copies to be his friends and used them to go on several crime sprees; making him one of Japan's most wanted criminals. Jin also abused his Quirk to create more clones to do all his work for him.

However, this soon backfired as the clones, being perfect replicas of Jin, began to rebel and claim that each one was the original. This resulted in them cutting Jin across his forehead then strapping him to a chair and engaging in a long, brutal fight that lasted nine days. Eventually, all the clones had killed each other and Jin was the only one left remaining. Since that incident, Jin has struggled to come to terms on whether he is the original or just another clone, and avoids serious injuries out of fear he'll disintegrate.

Sometime after this, he encountered a man named Giran, who told him that there are a lot of people similar to him in the world and recommended he join a group of these similar people, introducing him to the League of Villains, now assuming the monicker: Twice.

Twice eventually got over his own trauma, realizing that he is in fact the real Twice, and used that power to create an army of clones to help his friends, The League of Villains in the battle against another big villain: ReDestro.

Twice's Quirk: Double, allows him to create clones of people and things. Before creating clones, he requires the measurements of the person he plans to copy before he can actually create clones of said person. The clones themselves carry over the exact appearance and personality of the original person, even copying their Quirks. When a clone gets destroyed, they turn into a liquid substance and melt away. It should be noted that Twice has no control over the clones he creates. This was shown when he created clones of himself and the clones eventually turned against each other, killing themselves. If the real Twice is killed, then any clones he created before his death will melt away.

His Ultimate Technique is called "Sad Man's Parade", where Jin creates clones of himself, then the clones create clones of themselves, then those clones create clones of themselves. This cycle of exponential growth continues, resulting in thousands of clones of Jin.