[Unplayed Short Lines] Fantasy

Introduction
Da-jeong, a timid man who has a crush on White, the owner of a nearby flower shop.
On the same day as usual, Hayan and his cell phone are switched and he discovers that there is a strange app.
The main quest to target Hayan, the target of unrequited love, appears and Da-jung starts to move as the app wants.

[Success reward: Unbreakable eternal happy ending]
[On failure]: ????
And forced shutdown due to hidden keyword..?
“What is the hidden keyword?
And what if it fails...?"