The "Kohinata-tei Characters" or simply the "Kohinata Residence" (コヒナタ邸) is one of the four sections in the "Logicalism Characters" page in Logicalism. The characters listed in this section lives (or have lived) in the Kohinata's mansion. Some have appeared in the "choose your adventure game" in Logicalism, in the game "Kohinata-tei no Bansan", or in the web comic series "Kohinata-tei Kumi".
The newest character to be added into this section is "Kage" "Photon".
Kohinata's house has its' own section in Logicalism and it can be found in the 'artworks' section. Scroll down and you'll see a garbage can icon on the bottom right side of the page. Click on the icon and Fumi and Kohinata will appear. Wait and look for a chance to sneak in (隙を見て潜入する) and you'll finally reach his house.