Was able to get the scene after some experimentation. You basically need a near maxed out affection with Thomas. Follow this:
Day 1
- "Got it."
- "OK."
- "Well, I guess."
- "What do you usually do?"
- "Good Idea!"
Day 2
- "There is still time."
- IMPORTANT: Do not accept Charlie's invitation to dinner. This will close off Thomas' route forever.
- "Ok. Let's go!"
- "Well, it's hard to say, honestly.
- "You bet, man."
- "Yeah, why not?"
- "You have a big chest."
- "Yeah, well let me just feel it."
- "Way to go man. Let's get it started!"
Day 3
- "There is still time."
- Go to Thomas' room.
- "Good idea!"
Day 4
- "There is still time."
- "Ok. Let's go!"
- Go to Thomas' room.
- "She had a fairly successful debut. Now she is a diva!"
Day 5
- "There is still time."
- Go to the gym.
- "We'll get a room later."
- "Just keep going."
Day 6
- "Yeah, sounds interesting."
- Go to Thomas' room.
- "Knock on the door."
- "Man, you're cute!"
- "Dude, this is dope!"
Day 7
- Go to gym. Work out. Go back to dorm.
- "What the hell?"
- CG unlocks.