Hi Nikole! There's currently no walkthrough available, but thanks for reminding me- I'll make one soon and update in the devlog!
It should be pretty easy to get the bad and good ends of each route respectively though (Sol and Kisha have 2 endings each, and the mystery route has 1 end). Also note that the mystery route is only accessible after getting both Kisha and Sol's good end! Hope this helps and hope you enjoy the game~