A relationship is give and take. You make concessions for the things the person you love enjoy or wants to do. Ichikawa and Yamada have been doing that for each other for quite some time.
The school trip is a prime example of that. Yamada should have been at home training for the audition but instead she spend 3 of the 4 days there with Ichikawa, when Kyo noticed that he said to Anna that it was okay for her to go and return a day early to participate in the audiction for the role she really wanted.
Frankly this is one of the reasons why the romance in
The Dangers in My Heart is much better fleshed out than in most other romcom series.
Shame that some people here don't seem to understand that even after all this time.