Yeah i guess its her main flaw, she definitely is EASILY influenced by Leah and Danielle when its about the MC
And tbf you can play the MC as a kinda immature shithead who gets caught watching porn when the groupcall starts in the beginning and is annoyed at his friends for interrupting his porn time .... so maybe its not entirely unfair for summer to suspect the mc being somewhat of a moron.
Even less considering which kind of guy seems to be his best friend
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But she comes to her senses rather quickly and its not like their revenge was this bad of a experience for the mc (oh no random girl or random guy may sees him naked in a lake).
In her defense, they all didnt have any contact for .. dunno .. quite some time but yeah i dont disagree, it was utterly dumb
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but imo more of an excuse from the dev to build in a lewd scene, thats why the whole buildup is so dumb and nonsensical.
dev just said "fuck it, i need some reasons for the girls to play with his cock and build stalker horror tension" and that was the best he came up with in this situation.