There was an original world (world 1) where some wanted to share their abilities with other versions of themselves. They opened a bridge to world 2 but there were problems with the bridge. Dungeons (or was it some infectious monsters?) Traveled through the bridges and to other worlds. They began destroying them. Since the connections and corruption could be closed, world 1 passed their abilities to other versions of themselves. So every constellation is a version of themselves from a different world.

The system was developed as a way to manage the powers. World 1 was too lazy to develop it so they passed the development onto someone else in world 17.

Seheon 17's gang was trying to find this person. After some investigation, hara discovers that bokhee was missing and figures out that bokhee 17 was probably the creator.

bokhee is revealed to be trapped in a different dimension.

The system sends hara to complete missions to fulfil gaps in time. These missions are of hara's past (staring a while before she meets cupid). It's revealed that she caused the random problems and inconvinces in her life. She then starts playing the role of cupid but her thoughts and actions go through the systems' translations, angering past and present hara. She continues until the mission stops and she is sent to another dungeon. It's the dungeon that killed seheon's mother. She walks around the dungeon and protects his mother

in this version of the dungeon, seheon meets hara in the dungeon. They manage to save everyone in the dungeon. No deaths and leave. It ends up creating an alternate version of their timeline

seheon ends up completing hara's the system mission.

Seheon continues where hara left off and becomes hara's constellation and helps her while watching their interactions. His part ends when cupid disappears.

Its revealed that bokhee chose hara because some version of hara always meets some version of seheon in all worlds. Bokhee reveals that he need hara's help to defeat the corruption preventing him from leaving.

Hara fights the corruption and wins. She becomes sss class in the process

hara's move on skill is a dimension traveling skill. It allows her to move through dimensions once in a very very long time.

Hara and seheon also got a dimension traveling item after completing the fire dungeon (in the past) mission. Hara sends him away from the fight and he gives it to hara 17, allowing her to go home

hara views an alternate timeline where there were no casualties in the dungeon. She contemplates whether to make that their new reality because seheon might be happier in that one

Meanwhile, he had already refused because although he might have been happier, the person in that timeline wasnt him