Thalia never showed more skin than she had to. Even in the blazing heat, she was covered. To see her in anything but her leather jacket, black jeans, and combat boots was simply unheard of. The campers had always assumed it was simply her style, a statement of self-expression. Thalia never gave an indication that they were wrong after all.
Unbeknownst to those around her, Thalia hated her clothing. Not the colour or the style but the coverage. The black colour dragged the heat towards her and the lack of exposed skin left nowhere else to go. Summer practices were near impossible in the heat and yet she had to press on. She couldn't afford to lose the practice, not while she still had to prove herself capable. She pushed herself so hard every day that it was simply routine to have the Apollo kids nearby. Every meal she could be seen drinking more glasses of water than the campers could count, and yet she still found herself waking up on the floor of her cabin after passing out on more than one occasion. Will had told her she had to find a way to stay cool in the heat or she could risk serious injury but, no matter how many times she was told, she refused to change her clothing and there was no way in Hades she was getting into the lake.
Thalia was never the same after she woke up from her "tree nap" as she had heard some call it, and everyone could see it. Not only had she aged seemingly overnight only to wake up to a world that had moved on without her, she had not woken up in the same skin. Looking into the mirror in Cabin One, Thalia saw over a dozen markings forever etched into her skin. Bright pink words and drawings from the various campers who had carved into her tree while she was asleep, forever ingrained into her otherwise perfect skin.
Some were barely legible, done by a young Annabeth, long before she had gotten skilled with her knife. Although it took her a while, Thalia could make out the words 'MiSS' and 'SorrY' spread over each of her arms. Others were much easier to understand, such as the heart on her right thigh with a T and L inside. Thalia hated that one the most. Luke's betrayal had hurt her more than he had let the others know. She had to be strong, like always. She could never let them know she was in pain, just like she could never let them know about the scars.
Thalia could only imagine what the others would think. The markings on her body were not beautiful like tattoos but crudely done and in awkward positions. Not only would they whisper but she knew that some would blame themselves. Annabeth was already struggling with losing Luke, but to have to live with the knowledge she had scarred someone she had thought of as a sister? It would be too much for her to handle at once. Thalia refused to cause Annabeth any more pain than she had already.
So Thalia kept covered. She kept sweating all day, drinking more water than she could stomach in order to keep from passing out, and most importantly she kept quiet about it all. After all, summer couldn't last forever. Eventually, the heat would break and everything could go back to normal. Whatever that was.