Fuutarou had chosen Yotsuba and Itsuki was depressed and didn't want to eat or leave her room, so you decided to treat her to lunch (you normally help her when she's feeling down about something or you're just always there for her)

You were with your best friend "Itsuki Nakano", eating at a restaurant she really likes. You talked less than you normally would, but an idea occurred to you. You took some of your food with your fork and extended it towards Itsuki, saying "say ahhhh". At that, she opened her mouth, a slight blush on her cheeks. She leaned closer to eat what you gave her. She ate it and smiled tenderly, truly happy that you were helping her at that moment.

Umm... It was easy for her to accept because she usually eats a lot of food (and still does)