He can, with some help

Kurumu immediately reacted as the mermaids started going after every guy in the pool. She focused charm on her surrounding temporary harem, keeping the guys away from the side of the water as she headed for the boys locker room. "Tsukane, use Charm!" She shouted at Tsukane, the false incubus looking at her before trying it in a massive wave. He was able to stun most of the female swim club members, but not before two of them managed to bite into one of the new guys, the man aging before his eyes. Unfortunately, this distracted Tsukane a bit too long.

"An incubus!?" Ichinose responded as she shook off the stun from his charm, transforming into her mermaid form, the rest of the team doing so as well. Tsukane tried to apply charm again, but all of them were ready for it this time, mentally focusing to resist it. "Don't think too badly of us!" Tamao crooned, swimming about Tsukane like a shark. "Luring men into the water and draining their life energy... it's simply our way of life. Isn't it wonderful!?" She shouted as she lunged at him, leaping out of the water for a flying leap. Tsukane tried to fly out of the way, but as he grew his wings, he found them too wet to get any lift. To his surprise, instead of biting him, she simply wrapped her arms around him. "Don't worry, Tsukane, you're different from the rest of them. I've had my eyes on you since before the entrance ceremony. You smelled just like a human! I can't wait to eat you up!" She opened her mouth all the way (that is a lot of teeth!) and prepared to bite him. when suddenly -

"Tsukane!" Moka had jumped in after him, tackling Ichinose off of him. "Hah, glad I got her - ah!" The vampire said before almost sinking without knowing how to tread water. Tsukane reached under her arms and pulled her back to the surface, slowly kicking to try and move them to the edge of the pool. "Still need to learn how to swim?" He asked, Moka coughing a bit as she nodded in his hands. In another circumstance, she'd be loving the fact he was holding her under her breasts in her sexy swimsuit, but they weren't out of trouble yet. It looked like Ichinose was recovering quickly.

"Tsukane!" Kurumu shouted, diving towards him through the air. flapping her wings and holding... the lamp! She dropped it right to him before flying up again, trying to stay out of the mermaid's jumping range. 'It may not be the same as it used to, but we could really use your strength!' Tsukane prayed in his head as he removed the Rosary from the lamp.