This story takes place after The Last Problem, and as a result, Diamond Tiara, the Cutie Mark Crusaders, and all other characters that appear in this story are grown adults.
Ever since taking over the Rich family business, Diamond Tiara has been working hard to use her status for the betterment of everypony. She's come a long way from the stuck-up snob she was as a foal, but her family's reputation can't be forgotten quite as easily. No matter how much she tries to give back to the community, she will always be a Rich. For better or for worse.
Perhaps this is why her friends are suspicious of her new boyfriend.
And perhaps it's why she likes him in the first place.
Day #4 of Hearts and Hands Week.