In a nutshell, limerance is an uncontrollable obsession with the romantic relationship with a specific person. That "specific person" part is key: it's not obsession about romance in general, it's about a specific person. The person with the obsession is the limerant. The person the limerant obsesses about is the limerant object (LO). The other key concept is that the obsessions are intrusive; basically you can't stop obsessing even though you try.

I hope this information can help anybody else who is suffering through limerance like I do.