It helped that Kai couldn't think of any other reasons for Shinji to contact him. Especially at night time! Especially after he'd thrown that offer out there to the wind! And honestly he was just already used to only getting messages when someone wanted something. Business as Usual.

Kai had gotten himself out of bed though. There was the distinct impression that Shinji would be a little too polite to just wander Kai's house to find him if he did manage to let himself in. To make this process easier, Kai went ahead and propped the front door open before he wandered off into the kitchen to grab a glass of water.

Did he bother putting a shirt back on for any of this? No, why would he. This was sleeptime attire.