I have some suggestions, don't know if you would interested.

First option: ->First name: Yuu (unisex, pronounce "you") +Why I use this because as the game advertises "you" are the main character. ->Last name and IGN: (no opinion)

Second option: ->First name: (anything that start with a C) +Chika, Chito, Chiharu,... ->Last name: (anything that start with a M) +Mizuno, Morikawa, Matsuo,... ->IGN: (no opinion) _With Japan (Asian) usually write last name first then first name later, take the two first letter and it would be MC (main character)

Third option: _I tried to find name or simply just play with words to get a name that would connect to the word "change destiny" as the game advertises but I simply not good with Japanese enough to do it so... ->Failed Mission

*Extra notices: If you play as female and read through all the stories, koharu (and other characters) does address you as a female (though most of the story usually gender neutral). Most noticeable scene is the picture on Floor 1, and on Floor 2 there is a scene that Koharu basically wanted go yuri route with you, as well as the most recently bride event options. There are some more but this comment is already long enough.