The meeting at Cherry's exhibition and post-exhibition sex at Alison place has text variants for Ian/Alison in close relationship, so that covers them as a couple (or as causal hookup, depending on the player's choices) So... am not sure what you mean here, tbh.
edit: their conversation when
_love flag is enabled ends this way:
Python:
a "Well, I know you said you didn't want to get into another relationship just yet. But if you ever open a call for applications, you already have my resume, ha ha ha!"
i "I'll be sure to let you know when that happens..."
Is this what you're referring to? Alison is effectively leaving the decision whether they become official up to Ian. Later in the chapter Ian has some monologue about how they're getting really close. So i imagine if there's some actual decision to make, it's not far off.
edit2: there's actually interesting tidbit buried in the script for that scene. If Ian is dating Holly then this happens:
Python:
"If my relationship with Holly continued to go on, there would come a time where I would need to make a choice, and I could feel that time was near."
"They both had strong feelings for me, but I couldn't correspond both of them at the same time, could I...?"
I wonder if this means that Ian/Holly/Alison is potentially in the cards. That would be... interesting, i don't remember such idea around here.
