Crystal Vu is a Scorpio, and Buzz is a Leo. There is a strong attraction between the two - no matter what you do.
I made for Buzz a Scorpio CAS female, but Buzz was attracted more to Crystal Vu, may be he likes tan skin, and my sim was white skinned.
Crystal Vu defeated my other female sim, and married Buzz, although Buzz wanted to flirt with my sim too.
The next time I played there, I deleted first Crystal Vu from the game, and only then aquainted Buzz with my Scorpio sim...
.
There is another female - Margaret Howe - with which Buzz developed strong attraction. And the third is - if you resurrected her - Olive Specter (Scorpio too), which, in spite of their hatred, wants to invite Buzz to her house. I guess she killed Lyla because of Buzz...
.
When I want a strong attraction, I always create Scorpio/Leo couple.