Shirtlifter is an anthology series in which MacIsaac has focused on creating short stories and serializing long-form comics work, such as his graphic novel, Unpacking.

[15] MacIsaac's comics explore the varied facets of gay men's lives and experiences in modern life, including sex and sexuality.

[6] MacIsaac has said that he is less focused on arousing desire, but more "interested in how sex defines people, how it can be a sublime way of revealing character and motivation.

I think that’s one reason why, for gay men, sex is so often a path to or conduit for building friendships.”[8] MacIsaac's work has been honored by comics and literary professionals.

[6] His work has been collected in anthologies such as No Straight Lines[10], QU33R,[11] Alphabet [18](with Todd Brower), Stripped,[19] Boy Trouble,[20] Blocked,[21] and “Best Erotic Comics 2009.