Purple Protector by Catherine Lievens

When life gives you a one-time opportunity, grab it with both hands.

When Aaron is offered the opportunity to interview the king of the Eiloren clan, he can’t say no, even though he has no idea what he’s doing. He’s fascinated by the dragons, and in particular by one of them—Birch, a massive dark purple dragon.
Birch notices the human, but he’s too busy protecting his king and best friend to have time for one-night stands, let alone relationships. Aaron is tempting, but Birch knows better.
When Aaron is attacked, Birch volunteers to protect him. Everyone knows who’s behind it, but there’s no way to prove it, even though they’re a danger to both Aaron and Killian’s throne. Aaron proves himself impossible to resist, though, and when Birch falls for him, he knows that he’ll do everything in his power to protect him.

He might just have to.