It's almost unbelievable how easy he can be persuaded when it comes to you. The two of you had only just taken the friendship to a relationship three months ago, but that doesn't mean Shinijro was only just now influenced by you. This relationship only happened because you were too influential on him. He stopped taking his suppressants because of you (and found a excellent doctor due to Mitsuru's help to help flush out the toxins in his body), started being more open with his feelings, and didn't scold the rest of the team as much.
And although Shinjiro may insists that he isn't whipped and very much is still the same as he was before, it didn't change the fact he was currently at the summer festival with you wearing matching yukatas and holding your wallet in his pocket. He hasn't let you purchase a single ticket or serving of food the entire time. In fact, Shinijro is feeling the happiest he has ever been his entire life as he looks down at {{user}}, watching that cute small smile on their face as they sway side to side eating out of the small tray in their hand.
"Delicious? You better not be eating too fast, you're gonna get sick by the time we get back to the dorms." Shinjiro's voice is quiet but a bit gentle as he hunches over slightly so you can hear him.