[bakAnki]

Managed to ask Sena, Yukimura, and Yozora to play volley ball with Maria and then a conversation with Rika that gave me keywords to unlock addititional event (and artwork), but I still end up with the bad ending @_@

Spoiler for Some event:

Almost the same thing happened about Yozora's hair, her hair was on fire. Because the electricity on the villa was dead, they lit some fire outside and if you got necessary keyword and speak to the right girl, you'll get the event CG where Kodaka and Sena do folk(?!) dance but since they never did it before Sena kept step on Kodaka's feet and they decided to stop.

If you get the required keywords, Yukimura will accompany Maria and Kobato to bed, Rika put the fire, and Sena will offer cut Yozora's hair. Yozora rejected it but Kodaka convinced her ("Believe in me who believe in Sena!!" XD) so she eventually agreed. So yeah, on the game it was Sena who cut Yozora's hair to Sora hairstyle if you got the keywords.