FAIRY TAIL Vol 5

From the Kodansha edition

GRAY-OUT Gray’s old training companion Reitei Lyon is trying to revive a calamity demon, but doing so will make their former master’s sacrifice meaningless! What’s the secret of Gray’s past, and why does he keep taking off his clothing? Gray is revealed (metaphorically speaking) in this pivotal volume of Fairy Tail! Includes special extras after the story!

Source: Penguin Random House API