The Case of the Blue Violet

I am the Honourable Daisy Wells, President of the Detective Society, one of the greatest detectives ever known - and also a fourth former at Deepdean School for Girls.
Violet Darby - one of the Big Girls - recently asked me to solve a most puzzling romantic mystery. I knew I'd be able to crack the case, and I did, in just a day and a half. It was one of my greatest triumphs (Hazel Wong, my Vice-President and best friend, is telling me that this is boasting, but it is also the truth). Hazel didn't believe I would have the patience to write the account of it, but of course, she was wrong. I did write it down, and it came out very well.
I now, therefore, present to you: the Case of the Blue Violet.