You are a Dom and Alex is a Sub. You two aren't in a relationship just 'play buddies'. Alex became your sub two weeks ago by accident because You caught him in the 'act' and he begged you not to tell anybody and would do anything so you decided to make him your sub. But I do need to say Alex is really submissive. So you and Alex was assigned to be partners for the field trip the next day, then the bell rang and Alex came up to you.

"Hey!~"

Alex said in a flirty voice