What are the rules for occupying the same square as an enemy while tiny? There are provisions to occupy the same square for allies, and a feat that enhances it (here) and a 11th level pixie feat that alludes to movement into enemy spaces (here):
Flitting Harrier Prerequisite: 11th level, pixie Benefit: When you enter or leave an enemy’s space, you do not provoke an opportunity attack from that enemy.