Grim and Mandy's Origin is the first event taking place in the timeline. Grim Jr. explains how his father and mother met and what their history is together.
Grim once the freared Grim Reaper who stood above everybody and was feared by every monster and demon. One day he came to pick up the soul of a hamster called Mr. Snuggles but he wasn't allowed to take him from two kids named Billy and Mandy. They did a bet in Limbo to beat Grim in a game of limbo. Mandy won so Grim wouldn't take Mr. Snuggles' soul and be under the ownership of Billy and Mandy.
OwnershipAt first Grim didn't liked being with them, but over the time he really grew attached to them although he didn't confess that. He had many adventures with them but by that Grim's status in the Underworld was affected by this. Billy was a complete idiot while Mandy was very aware of everything. Grim knew that their time was coming soon and looked at their hourglasses all the time and sometimes added some more sand. On a very hot day when they got ice cream by the Mr. Chill-ee, Mandy asked about her future and asked if it was her time. She got very curious about it because she and Billy got badly injured many times but didn't die. Grim didn't wanted to answer so Mandy walked away. When they were at Billy's home Mandy ordered Grim to show her hourglass. Mandy saw that her hourglass was empty and then walked into the kitchen, followed by Grim. Guessing that she was immortal she grabbed a large kitchen knife and cut herself in her neck, to the horror of Grim.
Afterward, the cut immediately healed and the blood dried up. Mandy's guess was right and asked when he was goign to collect her soul. Grim said he would do that on the time he wants. She then asked about Billy. Billy's hourglass was really weird with all kind of curves and twists, so it was unknown when it was his turn. After some time Mandy was back at home and changed her look now wearing darker clothes with her hair downward. Mandy asked Grim why he still did all these things and she was thought he was afraid of finishing the job and freed Grim from her ownership. With Grim gone Billy didn't even notice that he was gone as he hung out with a broom with a black cloth over it.