What Do I Know?

Midoriya has a secret. When everyone did the showcasing of their rooms, he hid something from them. When they stood gawking at his All Might merch, he purposefully placed himself to hide his greatest treasure. Something his father had left for him before vanishing into thin air. Sure, he hid some posters too, just in case such an idea was actually conjured up by his friends (thank the stars he prepared for that), but it's not like knowing would change their view of him. Or at least, that's what he tells himself.

Ashido had seen something earlier. Midoriya, when displaying his room, seemed to be hiding something. She didn't really want to intrude but, seeing the open boy covering something with his own person made her ridiculously curious. Yes, she didn't need to fill Uraraka, Yaoyorozu and Jiro in on what she thought, but at least this way she had back up.