Percy
Percy couldn't believe what he was seeing. Nico's ex-boyfriend, turned murderer? Hiding in the bushes, he realized he had to do something. He didn't think Nico could fight for himself given the fact that he was literally dissolving. He had to think of something. Oh wait, Percy realized. The lake. Nico was about to get drowned, and here was Percy, a son of the water god.
"I really think I can," he heard Will say.
So he did what any logical person would do, and summoned a huge wave to slap the murderer in the face. With water of course. Then he summoned a gentle current to carry Nico to safety.
"Alright Will", he said, "You've got some explaining to do back at the big house."
Nico and Percy got out of the meeting at the big house because Nico was disappearing into darkness, and Percy asked to go with him and help with the healing process. Percy force-fed him some ambrosia as he slept in the Apollo cabin. He was giving Nico a third square - this stuff would probably burn him up, but right now he was just worried about stopping him from fading - when Hazel Levesque stuck her head through the doorway.
"I can't believe that Will did this!" she said
"I know, I thought he was a good guy" , Percy replied.
"Anyway, as long as he's unconscious, there's something I want to tell you." She ducked back out of the cabin.
" Umm... Okay", Percy said, following her out.