This question is way too broad for me to answer! Because they're amazing in so many ways! It's hard to pick just one “best” thing.
🥲 So my answer is “themselves.”
That feeling where “you understand what the other person wants without saying a word,” and “when you do speak, they get it instantly.”
As if their souls had been intertwined from the very beginning.
Simply put, just seeing them together makes me incredibly happy—like there's this magical, powerful attraction between them.

Thank you for liking my artwork! Regarding this question, I find it a bit hard to decide 🤔 They felt so familiar upon meeting for the first time, as if they'd been together for ages in a past life (?) So I'll go with “first meeting”!