Is there other media belong to the Sono Hanabira series besides the Visual Novels
The illustrator Peko, along with the other staffs who created the visual novels, published several dojinshis (not safe for work) that contained novels and illustrations (one copy of which I have). These might be considered official adaptation. Note that the visual novels themselves used to be distributed much like dojinshis (e.g., at comiket), and not like typical commercial VNs.