From info so far, the princess is planning on using it on herself, so she falls In love with the old dude she has to marry. So she won't be that miserable, and can marry someone "she loves"
Oooh ! Poor thing
damn... that's really sad...
Do not fret; some 'big' spoilers mentioned about the princess & the love potion:
Dw too much, she's a nice un.
She never ends up using it. Turns out the guy aged 60+ is a sweetheart and gentleman, and felt bad that she was forced into the political marriage arrangement with an old guy like him. He told he that she could live however she wants and that he wouldn't touch her or anything. The princess ends up falling in love with the guy lol, but he was really reluctant at first to accept her love, but things work out.
Umm. But he has grandchildren and a previous wife ! That sucks
Yh it does, but ig if she's genuinely happy then I can tolerate it.
The princess won't use the Love potion on our ML , right ?