"Aries-ponsible Friend" is the 15th episode of the AstroLOLogy animated series. It is the 3rd part of the Cat-astrophe chapter and the 15th episode overall.
Aries' doorbell rings and he sees that at the front door is Virgo with a sun hat and suitcase, who explains that she has a flight out of town for a vacation and needs him to look after her cat. Aries agrees, but soon after being given the cat, he turns out to be violently allergic to it, giving him hives and causing him to sneeze.
Aries puts on a face mask before feeding the cat, then offers to let it eat out of his right hand, but one lick of his hand causes his whole arm to break out and his eyes to redden, then he sneezes his mask off. Brushing its fur causes him to sneeze repeatedly, then he ends up brushing too hard and it bites his left hand, making it swell up, after which he collapses. While trying to clean it, the cat jumps onto a bookcase and refuses to come down for Aries, so he climbs up and ends up frightening the cat, causing it to jump on him and he falls off, followed by the bookcase falling on him.
When Virgo returns from vacation, Aries returns the cat to her, now with a tuft of hair and a red bow. She's happy at first, only to be shocked when she sees Aries covered in hives on his arms and face. He gives a thumbs-up, then sneezes, covering the screen in mucus.
During the fortune message, Virgo is poking Aries' unconscious body with a stick and the cat licks his foot, causing him to instantly get more hives on his lower leg, to Virgo's further shock.
"Even if it's rashy business, you can always count on Aries for all your cat cares."