Justin Trudeau calls himself Katy Perry’s “supportive boyfriend” - and he proved it in Madrid ❤️🎤 The former Canadian prime minister, 54, was spotted singing along to Katy’s latest hit, “Watch It Burn,” at Río Babel Festival. Safe to say he’s still her biggest fan! 📽️: katyperrycrave / TikTok #justintrudeau #katyperry