Author's note: I do not own Twilight and or any characters or plot lines in association to Twilight. This is for people who struggle to keep the relationships between my stories straight. More couples may be added as needed along with up dates.
The Twilight Relationship Diagram for calhale's Fan Fiction
Emmett and Jacob (See Sharing): After experimenting with his "brothers" (see After Glow) Emmett unwittingly admits that he has gotten Jasper off with a blow job after Jasper is hit with a super powerful lust wave and gets an epic boner (See Hybrid). This leads to Jacob taking advantage of the situation. Later before Emmett get's married again to Rosalie, Jacob and Emmett go camping, well Jacob follows Emmett who is camping and the hormones take over (see Sharing: chapter one). Read the rest of Sharing: an Emmett x Jacob Story to get the scoop on their hidden relationship. Also read Toys: An Emmett x Jacob x Seth story to see how their relationship gets discovered.
Edward and Seth (See Lonely): After Edward is broken in by Carlisle and his "brothers" (see references in Wrestle: An Esme x Rosalie Story and details in After Glow), Edward is left as the stay at home dad of Renesmee after Bella runs off with Alice (see Seat Belt and references through out several stories). Seth comes to Edward's house late at night in wolf form. Having forgotten clothing he is forced to wear a pink silk robe that once belonged to Bella. Long story short they have adorable loving sex and Nessie gets two daddies and two mommies. They are pleasantly out to the family as a couple. (See Sharing: chapter four and Toys.)
Side note for Edward: Edward was also raped by James while trying to lead James away from Bella's real scent. (See Mine: an Edward x James Story)
Bella and Alice (See Seat Belt): After Alice gets a very vivid vision (nice alteration) of Bella and herself in a very sexual state she vows to never let it happen until her seat belt gets caught in Bella's truck and she's kind of forced into having a sleep over. Their relationship however does not get serious until after Nessie is born.
Side note for Bella: Bella's real reason for leaving Phoenix was that she was raped by James (see Phoenix). She also had a brief affair with Rosalie (see Safety) due to Rosalie's fetish of liking to tie people up.
Rosalie and Leah (see Scouting): Rosalie and Leah hated each other until the day that they realized they had a lot in common. What happens when two girls with strong tempers get into a relationship?
Side note for Rosalie: Rosalie is kind of a whore. She slept with Bella (see Safety), Esme (see Wrestle), and several other people that I make reference to or haven't written about yet. However, Leah is slightly possessive and might kill whoever could seduce her lover if Rose ever cheated.
Jasper and Mike (See Overdose): Jasper loves teenage emotions. They are like drugs and Jasper likes to get high. No one at FHS is better at creating teen drama then Mike Newton. Sooner then later, Jasper finds himself addicted to the boy and Mike finds out that he maybe a little addicted too. (Also see references in Sharing and Lonely I think.)
Side Note for Jasper: Before Mike, Jasper was quite close with Emmett and they had a brief but loving relationship (See After Glow and references in Seat Belt). Jasper also had a very interesting experience with Carlisle (story in the works).
P.S. Carlisle and Esme still maintain an almost normal relationship as husband and wife, only falling prey to their "kids" every once in awhile.