Rika's Bug?
Suggested fix (unconfirmed): Walk Rika outside wearing the dog collar with four stops for poses, skip the minigame, and then trigger the scene in front of the choir the following afternoon while bringing her to climax.

2 fixes · 0 how-to answers · Steam discussions
Suggested fix (unconfirmed): Walk Rika outside wearing the dog collar with four stops for poses, skip the minigame, and then trigger the scene in front of the choir the following afternoon while bringing her to climax.
Suggested fix (unconfirmed): Make Misa reach climax one more time to trigger the achievement if you have already met the requirements.