I'm delighted you enjoyed it! About these 3 side characters, it depends on the community. If there is enough interest, I may consider it.
Chain is one of the most mysterious characters, so I wanted to at least add a bit of his personal life.
That line of Roya is not edited out. I think it was in Kurato's route where he said it.
Lioji's popularity still surprises me. His role as friend is on equal part with Ikuya.
There are many references spread through the routes. Kudos to you for catching this one!
No worries about your English, I understood everything well ^_^