From Wikipedia,
Virtua Fighter Kids is an installment in the Sega AM2 Virtua Fighter fighting game series. A super deformed version of Virtua Fighter 2, it was released in the arcade and on the Sega Saturn in 1996. Unlike Virtua Fighter 2, it was developed on the ST-V board.
All the characters all have big heads, and the music is a faster pace. The gameplay itself is slightly tweaked from Virtua Fighter 2. The Saturn version includes some new FMVs and programmable button sequences to allow players to test and use pre-made combos. Despite being children, some of the fighters retain adult characteristics, such as facial hair, muscles or
breasts.
One of the variations of the boss character, Dural, features her with a fishbowl for a head, complete with a fish swimming inside.