Bear is a quiet, insecure retail clerk who spends his days pining after his longtime friend Nikki. When he discovers that Nikki is casually seeing another guy, Bear falls into a deep depression. While browsing a dusty novelty shop, Bear finds an odd packaged occult twig labeled the One Wish Willow. Desperate and emotionally reckless, Bear snaps the wooden branch and wishes aloud that Nikki would love him "more than anyone in the whole world." To Bear's astonishment, the wish works immediately. Nikki shows up at his apartment that very evening, declaring her undying devotion to him. For the first few hours, Bear feels like the luckiest man alive. But subtle cracks appear in her personality. Nikki never blinks, repeats affectionate phrases with robotic cadence, and refuses to leave his side even for a single second. As days pass, Nikki's behavior escalates into violent obsession. She smashes Bear's phone, glues the front door deadbolts shut, and violently attacks Bear's friend Ian when he comes over to check on him. Even more horrifying, Bear notices moments where Nikki begins to hyperventilate and weep silently while her mouth continues to smile. Bear realizes the horrifying reality: Nikki has not fallen in love with him. Her conscious mind is trapped as a screaming, helpless prisoner inside her own skull, while her physical body is being puppeted by the dark magic of the wish. Desperate to undo the damage, Bear dials the customer support phone number printed on the One Wish Willow box. An ominous operator connects Bear directly to Nikki's true internal voice. On the other end of the line, Nikki is sobbing hysterically, pleading with Bear to reverse the wish and release her from the endless agony of forced obedience.

Faced with the opportunity to save the woman he claims to love, Bear's deep-rooted selfishness reveals itself. Instead of asking the operator to cancel the wish and set Nikki free, Bear asks if there is a way to simply "tone down" her clinginess while still keeping her in love with him. He cannot bear the thought of going back to being alone, and he fears facing Nikki's hatred if she regains her freedom. Hearing Bear's pathetic hesitation, the operator informs him that the wish can only be undone completely or left active as it is. Horrified that Bear still cares more about his own happiness than her suffering, Nikki's true voice screams in despair before the phone line goes dead. The movie ends on a bleak, chilling image. Bear sits on his sofa in silence, completely trapped in the nightmare he created. Nikki stands beside him in the dim living room, staring straight ahead with empty, glassy eyes and an agonizing, frozen grin on her face. Bear got the absolute devotion he wished for, but in doing so, he destroyed the woman he loved and condemned himself to an eternity of guilt and fear.