Oh this is a lovely idea <333
I imagine poor Legend would probably need some convincing that yes, she really is there and she isn't going to disappear this time. Once he does accept that though, oh man, he never leaves her side. The others have never seen their Vet so happy before and it lifts their moods every time.
Wars is especially happy for his brother. His meeting with Marin during the war had been weighing on him ever since he met Legend and learned that he was Marin's hero. Now that she's back, he can finally share his own stories of their time together without worrying about upsetting Legend.
Time often watches the reunited pair with a fond, if slightly homesick, smile. He's happy that another of his boys has found their happiness again. He's also amused at the growing trend of a preference for redheads in their little group.
Twilight... is a bit quieter now. He's happy for Legend too, but that red hair is still painfully familiar. He tries to keep his thoughts to himself. The last thing he wants to do is hurt his brother with his jealousy. Legend, of course, knows exactly what Twilight is thinking and eventually confronts him about it. The two have a good, long talk about it, and eventually Twilight is able to warm up to Marin.
One day, Wild, Hyrule, and Wind learn about Marin's mischievous side. They are ecstatic. The others gain ten more gray hairs overnight trying to keep this new group of four from causing chaos everywhere they go. Wild uses the sheikah slate to pick Legend up by his bracelet to reenact Marin's story about picking up the trendy gamester. Legend screams bloody murder during the whole thing.
That night, however, he's still found snuggled up next to Marin. No silly prank would ever make him regret being with her again. <3
