Chinami
for multiple reasons, trying to guess at Selly's bullshit, she was in wizard Maya's position, also, there's been other flags for Chinami but none for Tsukasa yet. I also think, given those flags, unlocking dicking Chinami is a deliberate multi stage process for Akira's journey and the player is being given multiple false options to trip them up from the 'true' path. Lastly, as much as i will laugh my ass off when Tsukasa's face contorts when she gets Akira's enormous cock shoved in her, i feel like Chinami is going to be harder to unlock than her, she's pretty text book ripe for grooming whereas Chinami only really has 'before i die' as a path for her to 'consent', Tsukasa will do it for a
crumb of affection.