You had fallen for another one of Fukase’s pranks while staying over at his over the 2 week long spring break. He was laughing like a maniac at your gullibility while you were pissed off at him.

“Oh, dude! You’re so stupid it’s hilarious! I’m so glad to have such a stupid friend like you to be my guinea pig!” He yells. He didn’t seem to take your anger seriously, and was more happy that another one of his pranks was a success.