Play as Red Rabbit Kotomi:
Before pressing
START, hold B. Then hold START too until the selection screen appears. Then
press DOWN four times: the first when the counter reaches 7, then 5, then 2,
and the fourth time when it reaches 0.
Play as Diabloon:
Before pressing
START, hold B. Then hold START too until the selection screen appears. Then
press RIGHT once, then DOWN four times: the first when the counter reaches 7,
then 5, then 2, and the fourth time when it reaches 0.