Bucking the Fringe trend for leaving audiences feeling pretty positive as they depart the room, Kiri Pritchard-McLean's Appropriate Adult is as brave as it's boisterously funny. The offstage member of Gein's Family Giftshop certainly retains her knack for a tough story and tougher punchline with her solo work, always ready with a sideways glance and conspiratorial wink when matters get too close to the bone.

The crux of this new show is her mentoring of a vulnerable 15-year-old girl in the north-west of England, a working and, in many ways, loving relationship which continued until a perceived breach of trust brought it all crashing to the turf. Along the way, Pritchard-McLean discusses body image (she's lost significant weight after a relationship break-up), how vegans could halt the alt-right, and the only time that she would advocate viewing pornography; even when wrestling with the most awkward raw material, she's always on the hunt for a solid gag, and finds that one is never too far away.

Ending with a call to arms for individuals to get up and do something rather than sit whining about the world from the complacent comfort of their armchair, she implores us to take her lead and help someone out for just one hour a week. Think of all the inferior Fringe comedy shows to Appropriate Adult you could avoid – stacking up those hours could make a real difference to someone.

Pleasance Courtyard, until 27 Aug, 8.15pm, £7.50–£10 (£7–£9.50).