That's very dedicated of him, if it makes him feel better for taking the time to post a video about an accomplishment that's so useless that it makes Anime cosplayers look like Nobel prize winners, let him enjoy it.
Then stop writing to him? You're just giving him more attention and more things to ego about, you could just stfu and he'd eventually realize what a miserable degenerate he is, you're being just as stupid only by replying and making more excuses.