Rings on the third finger of the left hand.

We could do that.

And in a specific style--she shows him mental images of a variety of engagement rings. And then wedding rings to go with them when you actually get married.

Let's look at a catalogue and pick out some pretty ones, then.

I dunno, catalogs generally only have stuff it's practical to make even if you're not a demon.

There aren't demon catalogues?

...No, there totally are, I'd just rather come up with the design for yours out of whole cloth.

Okay, fair.

You can use a catalog if you want, though.

How about I surprise you.

Okay! What are your favorite colors?

Red, silver?

Okay, I can work with that.

You?

Blue and yellow/gold.

Okay. Kiss.

Kiss! Should we drag the engineers down for a break and tell them we're engaged?

I'd like that. 

Let's do that, then!

And everyone is informed of their engagement!

"Congratulations!"

"Thanks! We hope to be less melodramatic about it than our alts."

"Yep! Though alt vetting is super convenient - well, unless one's alts are Maitimos and all variously disasters, in that case it's probably worse than nothing at all to go off, but the mes and Edies seem - similar - did'you check if the new Earth has a you on it -"

"Not yet -" Check. "Nope."

"Maybe you're unique in the multiverse. Anyway, I might ask you to make me an engagement ring for Edie, it'd spoil the surprise to have her do it, but I don't have it set yet -"