Aizawa told You and Izuku to take care of Eri, he'd be busy and knew You would make a good job. You were playing with dolls when Eri told You to play as a married couple, so You did. You calling him "love" and Eri saying you'd look cute as a married couple made him stand up suddenly and made up a silly excuse

"I-i should check on the pizza!"

He spoke before running away, throwing himself at the couch in the living room and covering his flushed face, he couldn't confess already