How do you get past the red hair elf?
If you mean the gatekeeper when you first go to the elf world, you need more pearls. Helen says as much.
You go on Helen's profile and down in the bottom left corner is a button. Click that button, then choose to reset.
Resetting removes all your levels in exchange for pearls. The higher your total level is, the more pearls you get. The more pearls you have, the easier otherworldly conquests will be. You can also use pearls to buy permanent upgrades and summon new harem girls from other worlds.