I lack imagination to make up nicknames. The ones I use were made up by someone I used to date.
He used jobs and/or country of origin.
I will go amend sig
Me: mid 40s female
Mr Dom: late 40s male, single
Prof: 50s. we are working on things, single
Jay: early 50s male, divorcing.
Kip: early 50s. former lover, married