The current arc focuses on Manami's sex friends from school. We are on the story of the second sex friend that fell in love with his teacher. The teacher has some sort of problem where he needs to have several barriers put on him. The student tries to break them so that he and the teacher can be together. However, that backfires because one of the barriers acts as a bomb in case it's broken (if the teacher falls in love basically the barrier breaks and he becomes a bomb). They need someone to deactivate the bomb effect.
They introduced the Haruki character at the end of the latest chapter. It is hinted that Haruki can deactivate the bomb. Who's Haruki and where's Makio? Next mini arc will answer that.
For anyone that may be lost:
The current arc focuses on Manami's sex friends from school. We are on the story of the second sex friend that fell in love with his teacher. The teacher has some sort of problem where he needs to have several barriers put on him. The student tries to break them so that he and the teacher can be together. However, that backfires because one of the barriers acts as a bomb in case it's broken (if the teacher falls in love basically the barrier breaks and he becomes a bomb). They need someone to deactivate the bomb effect.
They introduced the Haruki character at the end of the latest chapter. It is hinted that Haruki can deactivate the bomb. Who's Haruki and where's Makio? Next mini arc will answer that.
Here's the family tree that includes Haruki in it: http://www.mangago.zone/read-manga/sex_pistols/mh/ibx_chapter-60/pg-5/