ganma has the raws but you need the app. the boyfriend has beef with eita and he and the parttimer were making fun of eita for being a nekama to which yui was like omg isnt it dangerous for akane to be in a guild with someone like that. akane, obviously not enjoying her time gets up to leave and yui runs after her, giving excuses to explain why her bf and friend were being rude. akane blurts out that yui should break up with her bf (in her head she was thinking about how yui was always complaining about the bf and seeing him irl she doesn't think he's a good person) and yui slaps her saying 'what do you know about him' 'yes i complain about him all the time but that doesnt mean he isnt nice at other times' 'stop poking your nose in other people's business' (all of this is paraphrasing). and then she goes and tells akane about the first time they met up together and yamada came along, and when akane was in the washroom she was making advances on him (i.e. putting her hand on his leg) and how they were getting '''close''''. so akane hit her back and the rest is as you said.
Cant remember where I saw the raws but there is one panel where Akane was pulling the girl's hair lmao Yamada and Eita arrived on time to probably stop the cat fight, or something like that. Didnt see any convo so i dont rly know what is happening lmao