I am his... "playmate"?

So I've had quite a lot of dates with this guy the past few months. We haven't had sex yet, but we get pretty intimate. Anyway, he's busy prepping for med school so things have slowed down. I've given him his space and haven't seen much of him. I didn't see him for a few weeks, then he texted me. Anyway, I met him in a language class at my uni and I told him the only word I remembered was "to erect". He texted back "you would remember that. u did it enough times. ;) " i responded "hehe" and he texted back asking "did u find a new playmate? lol" why did he ask that? what did he want me to respond? he just turned 24 last week. anyway i assured him i hadnt and then he asked if i was free to hang out.