So Clevin is actually Patrick-aka-Menace who uses his psychic powers to make people believe in a projection. (Remember how Clevin works the projector in a cinema? It's a cute little joke about how he is, himself, projected.) Mr Gurwara was another of Menace's illusory puppets.



And the weird flashes of psychic pain and some little dog too? It's also Patrick. He's being attacked by something and calling for help. Since he's still intent on using the Clevin persona once things calm down, he found a pretext to make him disappear without arousing suspicion.