My Study Buddy Confusion

I recently started working with this new study group for my grad school classes. One of the members, Alex, is always cracking jokes and has this casual confidence that I secretly admire. We've had a few late nights where we've stayed up discussing course material, and every time it feels like there's an invisible line between friendly banter and something more. It's ridiculous because I know Alex just sees me as another grad student, but my brain keeps throwing these fantasies into the mix. I feel so silly and can barely admit this to myself.