The person/people you are jealous of when you're with your significant *fictional* other -

Luther:

- Allison, Luther and her love each other so much so naturally you're jealous

Diego:

- Lila, the chemistry and the similarities between Diego and Lila make you feel threatened

Allison:

- Luther, the same reason why Luther's date would be jealous

Klaus:

- Dave, the two literally made out like how many times???

- Ben, it's just that they spend soooooo much time together

- His metal flask full of booze, you wish you were the booze ;)

Five:

- Delores, and she'd be jealous of you, boo

- The Handler, he's always rambling on about the Handler and not enough about you

-  Coffee, same reason why you're jealous of Five and Klaus' booze

Ben:

- Klaus, Ben and him spend so much time together

- Jill, when Ben possessed Klaus, he tried to do it with Jill so the jealousy is just--

Vanya:

- Sissy, the affair ._.

- Leonard, hear me out, you'd be jealous because of the fact that he and Vanya dated and he had the fucking audacity to kiss your girl (and use her)

- Allison and Five, Vanya and them spend time together and talk a lot so sometimes you feel out of the loop (I would say Klaus, but why would you be jealous of Klaus? He's Klaus.)

- Her violin, you wish she played with you like she does her violin ;) (im dyring typing this lmao)

Sissy:

- Vanya, again, the affair

- Carl, the same reason Vanya got jealous of Carl in the first place, Sissy and him slept with each other

Lila:

- Diego, the same reason why Diego's partner is jealous of Lila