People who do quick transmigration come in all kinds, and not everyone stays with the same person forever like they do in novels.
We're merely humanoid lifeforms with nearly endless lifespans. Playing other roles is our job.
Some of us are flirts who hook up with someone new every time we enter a world. Others are obsessive freaks who cling to their partners and refuse to let go.
Of course, both types are perfectly normal around here.
Most of us, though, are ordinary employees like me: if we hit it off, we date; if we don't, we fake our deaths and disappear.