On Eren's birthday, Reiner does his best to make it an unforgettable day. He tries to make it loving. Sweet. Sexy. Exciting. He may overcompensate, too determined to make it good. Or maybe his determination helps, adding sincerity to each action, his focus on his Eren's happiness.

But at some point, he becomes distracted. A photograph he received intrudes on his thoughts, golden eyes growing distant even as he gazes into green, his brow knitting. The desire inspired by that photograph isn't bad—far from it. It's just… It's impossible. Isn't it?

Maybe Reiner and Eren are getting ready to go out when it happens, or else returning home. Maybe Reiner is cooking, the scent of meat and vegetables filling their house. Or maybe Reiner is unwinding a long-unused soft rope with shibari in mind, his distraction all the more apparent.

Whatever the case, Reiner comes back to himself with a fresh intensity filling his eyes, pain and longing making him blurt:

"I want to keep this."

Which makes perfect sense in his head, but may not make much sense coming out.