Is it still illegal to make a t-shirt with the cover photo of an album, even though I'm not selling it or anything?

So I'm thinking of making myself a G-DRAGON Heartbreaker (picture below) t-shirt (not to sell or anything. just to wear.) nut I've been told by someone that it's illegal, although I'm not planning to sell it online or anything (so I don't see why it would be illegal)
so...uh, help? ^^;