The reigning OPBF Featherweight Champion of Thailand. Also known as Scratch J, is a boxer from Thailand who was previously a Muay Thai champion, he has a very powerful right hook. He was the first boxer defeated by Miyata's Jolt Counter, while he was training in Thailand, as part of his travel to gain more experience. Sisfer comes back later in the series with his face full of scars and his speech slurred as Thailand's Featherweight champion to fight Ippo. In the fight, he reveals a devastating new blow that has the destructive power of a Jolt, without actually being a counter, named the Tornado Jolt. However, he loses by KO when Ippo uses a variation of the Dempsey Roll that uses an uppercut/smash instead of a hook. Jimmy Sisfer currently holds a record of 38-8 with all 38 wins by knockout and is based on former Junior Bantamweight champion Khaosai Galaxy who had defened his world title 19 times.