Well, I'll add some more information found in the old wiki for this game.
"The Hunt is the capacity of Aisha to unlock ero scenes on the map. Aisha gains the ability to sense ero spot where she can use her seduction skills to get more Lust than in normal seduction scenes, and then she can move forward the scene to something sexual.
Each scene of The Hunt has two requirements, these requirements can be to have certain clothing in the wardrobe, to have unlocked certain Special Abilities, or to have certain objects, etc. Once Aisha fulfills the requirements, she can access the scene. Each scene only appears on certain days and times, so not all of them are available at the same time.
To unlock The Hunt you need.
- 1- Start “My Friend and his Sister” quest, to get this done, you need two Lust Hearts and then sleep and the quest will begin.
- 2- Unlock the grimoire system. this is easy, just go outside Aisha’s place after starting “My Friend and his Sister” quest and Greg will show up, giving you a grimoire and unlocking the grimoire system.
- 3- Seduce five times. After unlocking the grimoire system, just do de action “Seduce” any place and when you do five, you will earn the grimoire “The Lust Seeker”.
- 4- Craft “The Lust Seeker”. To do this you need “Aisha’s own juice” (you can get them through masturbation in her room or while taking a bath in her bathroom) and a “Wine” (you can get it on the Store).
With the Lust Seeker, you can go to the map and the icon for The Hunt will be available when you click it it will show up all the available scenes."
Regarding point 2: Greg appeared outside the heroine's apartment only at midnight and only with 3 hearts of lust.
Perhaps there may be more, but definitely not less than 3. With 2 hearts, the event with Greg near the apartment did not start in my game.
Only after that the grimoire system and several quests became available. Also in the morning there was another event with the neighbors, which added another quest with the cleaner.