Singer Katy Perry has paid tribute to a superfan named Ralph Gierens, who passed away on May 10.

Gierens, who was a self-proclaimed oldest KatyCat (name for hardcore Perry admirers), hailed from Winfield, Illinois and died at the age of 69.

The news of his passing flooded the social media with trending hashtag #RIPKatyCatRalph, which also garnered the attention of the Chained To The Rhythm singer.

She wrote, "An angel got his wings today, love you @OldestKatyCat and thank you for your laughs and your service #RIPKatyCatRalph." 

Perry even changed her Twitter handle to #RIPKatyCatRalph to honour her fan.

Gierens was a Vietnam veteran, who earned a Purple Heart for his service in the war, reported Billboard.