Well, in the 'Rent a Girlfriend' full story, first of all, the desperation of the male lead to have a fake relationship is a key. He is pushed by external factors like family's disappointment in his single status. Second, the character of the girl who agrees to be rented. Her reasons could be financial or she might have her own motives. And third, the development of their relationship over time. How they handle different scenarios, from casual outings to more serious family meetings, and whether their feelings for each other start to change from pretense to something real.
The key elements in the 'Rent a Girlfriend' full story include the initial agreement. This is where the whole story kicks off, with the male character seeking a girl to play his girlfriend for a fee. Then, there are the family and friends' reactions. Their responses to the so - called relationship add drama and complexity. And finally, the personal growth and change of both characters as they spend more time together, which might lead to a shift in their relationship from a fake one to a more genuine connection.