I am doing the serial romance aspiration right now too, but I'm doing it within a challenge that I'm telling a story for, so it's been hard to slog through that way since I have to keep trying to tie it into a bigger narrative haha. In general though, you can plow through it pretty fast. If your sim has some reward points, you can buy the "beguiling" trait and that makes it SUPER easy to romance sims, which already isn't that hard haha, but it makes it go even faster.
@greydonn I didn't realize that the "kiss hands" interaction counts for a kiss! Honestly that's gonna make things just a tad easier I continue through this aspiration haha