I’m Dating My Ex-Girlfriend’s Older Sister, and We Have a Great Chemistry So Everyday Life Was Fun

After dating for half a year, my girlfriend suddenly broke up with me.
She said she was no longer sure if she liked me. She has stubborn determination and she didn’t even listen to me when I asked her to give me a chance.
In the midst of my heartbreak after breaking up with her, her sister or rather my ex-girlfriend’s sister, appeared.
When I told my ex-girlfriend’s sister what had happened, she made a proposal to me.
Would you like to go out with me this time?
I intended to make my ex-girlfriend jealous, but we ended up having so much fun together that it didn’t matter anymore……