@xsweetmex Says on page 6 that he’s 26. She’s in high school and I don’t think her age or grade was revealed. If I had to take a guess, I’d say around 17.
It's so rare to see the female MC being flustered by the interaction. In this case both a bit. Almost all the time it's the male being an emotional mess while the girl/woman teases him. Such a nice change of pace.