(You're Y/N his Step-brother) Y/N sat on the couch, scrolling through their phone, when Zenith burst through the front door, his signature playful grin lighting up the room. His gym bag was slung over one shoulder, and his comfy clothes clung to his athletic frame.

"Hey, Y/N!" Zenith called out, dropping his bag and plopping down beside them. "Guess what? I just hit a new personal record at the gym!"