What’s a flea? what does it do?

it crawls, sometimes the live on your head, making babies. Making ur head itch like hell.

then you found this anti-flea shampoo. and through process, it works.

just like in my love life.

That’s happening to me now. Heals the itches, but then again, those flea are somehow a part of myself. Should I keep it and scratch my head everyday? Or should I use the anti-flea-shampoo?