Back in the day, I've seen character profiles that include NPC love interests, usually created by the player for the purpose of their character having a significant other. In terms of generic dark histories, that love interest may be abusive and may vanish from time to time, only to reappear and abuse the character, who would be strangely nonchalant about it. That character could be kidnapped, raped, and tortured, but they'll only focus on how mind-blowingly awesome the sex was.
Those types of love interests sometimes coincided with players who had god-mode characters. The love interest wouldn't necessarily be connected to their god-moder (who was usually either a villain or a main hero), but to a secondary character, the dark-and-broody mysterious trope of the group.
I've also see characters created for the sole purpose of being a love interest of another player's character. They generally come off as clingy.