Mikey had Chuunibyou syndrome, or second-year syndrome. He just liked his make-believe worlds and doing whatever he wanted. Sometimes it was cute and funny, other times it was concerning. Grandiose delusions like fake 'powers', secret knowledge, etc.

Mikey never thought much of what other people thought of it, just focused on his friends. He liked that you indulged in it though.. it made him feel better.