I knew it! This Gohzou dude is a scumbag. If only Fumi or Ema revealed what happened in their past with this Gohzou, this childhood friend drug and grape would not gonna happened. For the MC, I don't have high hopes for this dude; maybe he will realize it after his childhood friend has already broken... For now, the chances of his childhood friend getting saved are that Fumi interrupts it and sacrifices herself instead, or something plot event that we don't expect.
Edit* After reading back ch. 31; the way Fumi was talking about this segg scenario of hers, looks like it's canon now after reading this chapter... I wonder why they keep all this a secret and didn't even report it to the police.