Mullin Shetland is a 19 year old musketeer aboard the Claimh-Solais (Mad-Thane's ship) His dream is to collect 20 battle survival medals (which he does in the end)

Throughout the series Mullin seems to be looking for a love. He hits on Lavie, Tatiana, and Dunya.

Mullin is first introduced when the Silvana docks at Walker's ship port where he meets Lavie. Here he tries to get reassigned to the Goliath but the captain insults him for being aboard Mad-Thane's ship and tells him his medals means he fled from battle. He is almost killed when he responds saying the Goliath is full of cowards because they flee battle but is saved by the Silvana crew.

Mullin joins the crew of the Silvana and is made a mechanic. However, he realizes that he is truly a musketeer and rejoins the Anatoray. While training to retake the Anatoray claudia units, he meets a Disith musketeer named Dunya and hits it off with her.

He almost dies during the claudia unit mission but lives on to have a boy and a girl with Dunya.