The Unexplored Summon:// blood-sign

is a Japanese light novel series written by Kazuma Kamachi, with illustrations by Kazuki Yikawa. The series began publication on September 10, 2014 by ASCII Media Works under their Dengeki Bunko publishing imprint.

Synopsis
Summoning ceremonies can freely call forth even "those which lurk in the depths beyond the gods." One boy has top-level abilities even among the cutting-edge summoners who can use those ceremonies. He is "Alice (with) Rabbit" aka Shiroyama Kyousuke. But this strongest boy summoner has a single fatal weakness. Certain "cursed words" spoken by girls: "Help me."

When Kyousuke hears those words from Meinokawa Higan, a girl brought to the verge of death, he throws himself into a city where three great summoner forces clash!