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My assumption about Killian is that he has particular ways he likes to annoy Thancred playfully/flirtily ❤️
Yes. 😉
There are two I've thought about thoroughly, but I am sure there are plenty others that would feel quite "them" because teasing just generally feels like a solid part of their foundations.
First, as long as it's not a real mission with heavy stakes, Killian likes to make Thancred break character. I've said before that they are competitive, and one aspect of that is Thancred has many versions of himself he puts forward. So, if he's trying to be sauve to gain intel, or is being super charismatic with the Eorzean leaders, or is just trying to scope things out in the background, Killian might try to make him blush or laugh. In some ways it's a game they play, and in others it's how Killian reminds him he's more than the personality he puts forward. As for how he makes him break, it's either touch - bothering him with his tail (Thancred will NOT admit to be ticklish) - or it will be by saying something entirely outlandish.
The tail one matters though - Killian selfsoothes by wrapping his tail around himself like a hug, which extends to how he shows his love for Thancred. I usually try to pose them with Killian's tail also touching him in some way, so all of that is very intentional even if I am not good at it yet and fits with the flirtily portion of this assumption too.
For something more verbal teasing, he makes fun of his "scoundrel youth" because both of them are slightly products of their pasts, so its a little more common ground to talk about it than pretend its not there. Also his lack of flavor in his cooking and his "Sharlayan tastebuds" because Thancred will claim Limsan in that regard, and Killian will do a "suuure, sweety". In actuality Thancred does like flavor, he just cooks with a bit more survival and nutrition in mind rather than taste. Some of that is just from being on the run for a living.
Off limits for jests are: - his age (Thancred feels like Killian keeps him young. But he has the extra 5 years in mind, even though his physical body is only 7-8 years older than where they've estimated Killian, so they have to reconcile that juuuust a bit. Read: Thancred is sensitive about his age). Also - Being a dad. They can talk about it and they do even though it's hard, but it's not for teasing. Partially for the above, but also because it makes Thancred think of Ryne which churns forth as much sadness missing her as it does the happy memories.
feeling like this of late
XIV Heatwave Festival: Where are you?
From womanizer to girl dad, he sure has come a long way, eh? Courtesy of the lovely @raccoonium 🙌