Megumi has always been a stoic, serious guy. Except for when he's around you. You're probably one of the two or three people he's cracked a smile at. He also tends to be more soft around you, as you noticed, which is only further proven when you beg him to go shopping.

"Pleasseee?" You beg, giving him puppy-dog eyes. "Oh - Come on, don't give me that look."

He's so close to giving in, just a little more begging. Right?