So today I read a Merlin fanfic called Alliance by Shadowglove
link : s/5990787/1/Alliance
And I thought of something that might work with it? So the story line is that Merlin is from the woods and his father is forming an alliance with Uther. The difference here is that Merlin, is not compleatlay human. Some people of the woods have cross blood. So, merlin is a cross blood, of human and cat/wolf (you can chose, but cat is better) he has a human apperance but when he get really angry, cat ears and a tail are visible on his body. They also appear when he is in 'heat' (look this up).
This is before Arthur confesses to Merlin, Uther and Merlins father (Balinor) are at this stage, good buddies. They are in the throne room descusing plans etc. (Arthur is there looking bored) When Merlin and Morgana walk in, Morgan says something to Balinor and he turns to Merlin who calmly states
"Father, I must leave, it's started." - by this he means his heat, his cat daemon side is going into heat (for the imaginative amd playfull writers this is a good thing to toy around with) merlin must leave to go to a forest on the border of Camelot to wait out his heat, even though they are human, the people of camelot (knights included ) will feel the effects of this. Arthor demands to know where Merlin is going, and insists he goes with him, however Balinor gives Arthor a look and says its a matter of honor and privacy. That promptly shuts Arthor up. Outside of the throne room, Morgana says to merlin that she has seen some kind of disturbance with Merlin's heat.
Merlin leaves for the forest, but what he doesn't know is the Camelot patrols are going past that forest. The leader is Lancelot, and for some reason (make this part up) he sends the patrol back to Camelot while he goes into the forest. Meanwhile Merlin is in heat so he can barely move (be very creative with this ;) ) when Lancelot somehow finds him. Because Lancelot is human he is still effected by Merlins heat. If you want to add a lemon/lime/fluff in there go for it!
When they get back, Balinor finds out what happens, shouts at Merlin and Uther and Arthor want an explanation. So Balinor explains how merlin is half human half cat deamon. And how they go into heat. Arthor get jealous, very jealous and ends up hurting Merlin.
So that's all I've got, if you want to adopt this, please go ahead! But first get permition from Shadowglove. And write a review to say you are taking it.
Thanks! And sorry if this was a waste of your time.