The hunger games- divergent-lord of the rings-the mortal instruments-X men- doctor who-teen wolf-vampire academy- Merlin-the walking dead-TFIOS-super natural-star trek- Percy Jackson-Harry potter- DC comics-avatar the last Airbender
Vampire Academy & Harry Potter & The Maze Runner & The Chronicles of Narnia & Beautiful Creatures & The Hunger Games & The Mortal Instruments & The Lord of the Rings & Divergent & The Fault in Our Stars & Percy Jackson & Twilight
Now that deal with Aragorn & Eowyn wasn't really a triangle. Eowyn liked Aragorn but he didn't feel the same way. Not to mention that Arwen didn't even know Eowyn existed for most of the ordeal, from what we've seen, anyway.