"Its fine." It wasn't like Tidus was going to be very noisy. Riku was more worried about trying to sleep when he was so worried about Sora.
"Alright." He'd probably wake up anyway when Sora got up, and then either get up to run, or go back to sleep. It depended how he felt when morning came.
Riku knew Tidus was still in the room, and that technically they'd already said their goodnights, but that really didn't stop him from kissing Sora again and pulling the blankets over the two of them.
Part of him wanted Sora to realize what had really happened, but another part wanted Sora to go on believing his parents were alright. In a way, HE wanted to believe everything was alright. How could Sora's parents just not exist anymore? It was too painful to focus on, really.