Calum Hoodism is the uncommon condition, typically found in teenage girls or 22 year old who love the band 5SOS (5 seconds of summer). This condition causes the person to be obsessed/in love with the bass player, talk about him more often than not, stalk socials, have dozens of photos of them.. you get the point.
Person with condition: "omg did you hear?! 5SOS are going on tour, oh my god I get to see that sexy mf Calum Hood!"
normal person: "oh cool!"
PWC: "Omg I loveeeee him, everything about him is perfect, his smile, hands, voice, h-"
normal person: "oh my god, do you ever shut up about him?"
PWC: "no... I have Calum Hoodism"