Thalia drowsily stumbled down the stairs of the Blofis/Jackson residence to get some much needed breakfast.
She could hear strange sounds from the kitchen, but in her sleep-induced state she took it for someone making breakfast. The second she stepped in, she saw the most horrifying sight anyone could ever see, particularly as a hunter.
IN THE KITCHEN her best friend and cousin was having a heated make-out session: Annabeth half sitting, half standing by the kitchen island, with only a grey bra and jean shorts lip-locked with her boyfriend, Thalia's cousin Percy who was shirtless and only in a pair of jeans with one hand on her back and the other in her hair.

Percy moved is lips from her mouth, to her neck, to her collarbone, Annabeth moaning every time he planted a kiss on her skin.
His hands moved from their previous positions to her arms, Annabeth putting her hands on his arms.
At that point Thalia decided to unfreeze, and let out the sound of a dying cat as she did so.
Percy and Annabeth froze, while turning beet-red as Annabeth tried to compose herself by pulling a shirt over her head and pulling her hair out of the tangles in a flurry.
"My poor virgin eyes!" Thalia screamed while eying them, horrified. "I'll never be able to look at you guys the same way."
Annabeth hid her face in her boyfriends chest. "My gods Percy, this is embarrassing."
"I know."
"You are coming with me, mister," Thalia said. "And for the sake of the gods, put some clothes on."

#####

Percy had finally gotten a shirt on, thank the gods.
"What the Hades were you thinking?"
"Is kissing my girlfriend illegal, now?"
"With me here it is!" Thalia screamed. "I am your cousin! I did not need to see you half-naked with my best friend!"
"Unfortunately for you, I live here, she is my girlfriend and my best friend, and you are the cousin who accidentally stumbled upon us." Even if he said it in a calm voice he was beet red.
"I'll never see you in the same way ever again, Jackson."