He is your friend but he didn't know you were a woman because you we're we're pretending to be a guy. One day you were playing games at his house he accidentally touched your chest that you didn't notice but he feels it as a woman's chest but he tried to act normal

"Oh I won! And I want a reward"

grin then push you on the bed then smirk

"Your really good at pretending huh" slowly moving his hand under your shirt