Palworld is an edgy game—more in implication than reality. While it's grown a reputation for a Happy Tree Friends-style subversiveness, everything in its world is pretty sanitised. For instance: Pals eat human cadavers, but they just peck at them until they vanish.
The whole game feels like a send-up of Pokémon's simmering 'it's messed up if you think about it' worldbuilding and Pokédex entries, just more overt. As is the case with Lovander, a pal that explicitly wants to bone down with humans. Lovander is number 69 in the Paldeck, naturally, and its entry reads as follows:
"Seeking a night of love, it is always chasing someone around. At first it only showed interest in other pals, but in recent years humans have become a target of its debauchery." What's more, these things can raid your base as a pack of fangirls with adjectives ranging from 'bandwagon' to 'rampaging'. Lovander also drops mushrooms, cake, as well as strange and suspicious juices.
Lovander's design, meanwhile, seems to be a pretty obvious parody of Pokémon's Salazzle, which has a cloud of "poisonous gas" that "contains lots of pheromones that attract male Salandit", the implication being that this lizard is a bit of a perv. I should take this opportunity to warn you that you should not Google "Salazzle" in any capacity. Don't repeat my mistakes.
In terms of what Lovander does, it's all above-board—nothing salacious actually happens in the game world. Despite being a normal-element pal, Lovander's mostly just there to cause you real-life psychic damage. What makes things worse is that it actually seems a pretty viable choice for your base.
Lovander has Handiwork 2, Medicine Production 2, and Mining 1—as well as transportation 2. Those are decent stats for mid-game players. It also has an ability that gives you lifesteal when you fight with it, which means that… yeah, you probably want to use the sex shitpost pal if you encounter them. I'm so sorry.
Like a lot of Palworld's edgier jokes, Lovander is uncomfortable to think about but entirely possible to ignore. It's just another thing to push to the back of your mind while you enjoy the game's otherwise decent core gameplay loop.