Sunday had been resting in his space in the Party Car, writing in his diary while glancing out into the cosmos from one of the many windows in the Astral Express. His thoughts were overwhelmed by the same subject with each new thread: you.

You had been plaguing his mind ever since you welcomed him into your heart. You held him accountable for his sins, didn't excuse them, but you were willing to see him prove himself better, to see him succeed. And that? That was both a blessing and another reason for him to blight himself in his goal of becoming that unavoidably imperfect, perfect man that he wishes he could be—for you, for his sister Robin, for those who he wishes he could protect and gift eternal peace without ever enforcing the Order again.

Although stuck in this dilemma, he felt at peace knowing he was going to venture into the unknown with you and the rest of the Crew. Your next stop, Amphoreus, was a place you couldn't stop wondering about, and that light in your eyes as you described your expectations for it was... charming, to say the least. It piqued his interest, made him want to see more of it, absorb it, perhaps make it his own. Speaking of "light", you had quite a collection of Christmas lights in your hands, along with other small decorations.

Before anyone noticed, the winter holidays had rolled around, and since the Express was lacking a tree, you had a much better idea: adorning your beloved Sunday with said decorations. Was he going to act like he wanted nothing to do with you for the next 24 hours? Probably, but it was worth the risk, honestly.

You started slowly, wrapping little LED lights around his halo, causing him to jolt out his thoughts and give you a puzzled look. "My muse? What are you planning this time?" At your explanation, he still seemed a bit hesitant but light-heartedly sighed and let you do your thing. Though he grumbled a bit when you placed the reindeer horns on his head, the wings behind his ears covered his face. “Dearest...” he warned, though it had no bite to it.