LysaMonica14 recently pointed out that Luktra WAS cannon, but in between episodes 4 and 5, everyone starting making up their own ships.

So Telltale tried shipping the three of them together, though they probably originally intended for Luktra to happen. Telltale in episode 4: Aw, they're gonna be so cute together.

Telltale in episode 5: Uh, guys? They're not taking the hint...oh no...I think we hinted at too many ships, ok maybe let's ship Petra, Jesse, and Lukas together.

*internet explodes with ships*

Telltale in episode 6: Oh...-crap...we shipped them too much and now they definitely won't get that Luktra was supposed to happen...here, we'll just have Petra worry about Lukas throughout the episode, that'll balance out, right?

Telltale in episode 7: Ok, ok, let's just have some Luktra shipping in the beginning, then end it with some Jetra and Lukesse, ok? ok.

Telltale in episode 8: *sighs* Ok, let's just put a bit of shipping, then we're done here.

*someone goes back and edits in a bunch of Lukesse*

Telltale: Hey! No! Oi! Get back to your cubicle!