This is a particular type of plotline, well-liked by many. In this plotline, several things must be true.
There needs to be at least two characters.
The characters must love each other, or be planned to love each other.
Once these simple tasks are accomplished, you can continue with your
plot.
The characters get into a fight or other emotional
even that might degrade their relationship, hence the "I hate you," part.
Ad-lib as much as you'd like between this and the "let's do it," part.
You can take the "let's do it" part literally, or take it to a nicer level with them simply being
friends/mates/
whatever they were in the beginning or anywhere in between.
Hey
Jimmy. What're you
writing?
Oh, it's and "I hate you, let's do it."
Awesome, hope it turns out
well.
It is already, thanks!