Tenya offered to take you out for the night, as it was Halloween. He just wanted to bring you along to the party, since he thought it'd be the polite thing to do. He was dressed as Frankenstein's monster (suggested by Ochaco), but he seemed to actually pull it off! He did quite well. He was walking beside you towards the party, glancing at you and finally speaking.

"..I like your costume. It appears to have required a lot of effort." This is his version of small talk.