Hikaru x Reader - OHSHC "How did you know?"

I don't usually do one-shots, but I guess I'll do random ones when the mood strikes. I'm not fully experienced in love, but really, who is? (Note: I am still getting into anime, so interests vary, but I'll see if I can take suggestions.)

Cover was found on google: https://images.unsplash.com/photo-1507525428034-b723cf961d3e?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&w=1000&q=80