Poolside by J. M. Snyder
Kevin's had the hots for Danny from the start of the semester. They live on the same floor in their college dormitory, and Danny's flamboyant manner excites the sedate Kevin. When it finally looks like they're going to hook up, though, Danny disappears, leaving Kevin hurt and wondering what it was he said or did to chase him away.
Then Danny shows up at the school pool, where Kevin works as a lifeguard. He seems interested enough, but Kevin's been there, done that. What can Danny possibly do to convince Kevin he's interested?