Rap battle minigame
From Summertime Saga Wiki
The rap battle minigame is played in the park at the evening after first talking to Eve near the fountain, then to the gang that moved to the bench. Chico, Chad and Tyrone will be the opponents of this hip‐hop contest.
Instructions
A sequence of frames is displayed in a rectangle. Each new opponent add two more frames. You must memorize it within a specified time period (60 seconds in normal mode, 90 seconds in cheat mode). Then reproduce the pattern in order by selecting the corresponding icons at the bottom of the screen. The white bar indicates the remaining time.
Reward
Successful completion provides +1 to charisma.