3 Years of Service
Honestly their teeth seem like a bigger concern, I'd assume dragons can hold back their breath attacks but it would still be like playing the knife game with your dick.I'm going to jump in and suggest that we might be looking at the dragon blowjob question the wrong way... if it's a fire drake, yes, decidedly unpleasant. If, on the other hand, it's an ice dragon that burps, why then it's probably just like getting a blowjob from a girl with an ice cube in her mouth. Very stimulating. A lightening based dragon would be like using an electro-stim. An acid based dragon.... well, the agony and the ecstasy.
Moving on to dragon like creature... a hydra could probably give a rim job whilst deep throating and talk dirty at the same time - they excel in multitasking.
Jormungandr would probably offer a superb experience of erotic asphyxiation.
And a basilisk would probably leave you hard as a rock.