I have to say that I absolutely love how you add subtle jokes that might end up unseen 9/10 times, but for that 1 time you see it, it just gets you to cry laughing. Like how at a certain point the MC makes a joke about calling Yui a certain name, and the very next dialogue box where she reacts with horror, her name is changed to that. It's a "blink and you'll miss it" joke but I love it!