a glutton for punishment
From Longman Dictionary of Contemporary Englisha glutton for punishmenta glutton for punishmentSUFFERsomeone who seems to enjoy working hard or doing something unpleasant → gluttonExamples from the Corpusa glutton for punishment• Talk about a glutton for punishment.• Being a glutton for punishment, a few days later we rounded it off by doing the Danube Knee bend towards Budapest.• Steve Jobs is obviously a glutton for punishment.