Shishunki no Iron Maiden

Mayama Haruki and Himemiya Tsukiko have been childhood friends and neighbors for as long as they can remember, but after a girls-only meeting in fourth grade, Himemiya distanced herself from Mayama. Now in their 2nd year of middle school, Mayama has become an ero-freak who specializes in harassing Himemiya. Determined to unravel the greatest secret of girls, what happens on "that day", Mayama follows Himemiya and uncovers…!

41 chapters

• Chapter 41 — The Iron Maiden's Puberty
• Chapter 40 — Secret Base
• Chapter 39 — The Great Escape
• Chapter 38 — REMEMBER!
• Chapter 37 — The Truth Behind the Metamorphosis
• Chapter 36 — Observing the Observation Diary
• Chapter 35
• Chapter 34 — The Princess, Captured...!?
• Chapter 33 — Uneasy Days
• Chapter 32
• Chapter 31 — FUCK YOU
• Chapter 30 — Bye Bye XXX
• Chapter 29 — First Confession
• Chapter 28 — From Pure White to Purity!
• Chapter 27 — The Second Album
• Chapter 26 — Charm Maiden
• Chapter 25 — If the Tears Poured
• Chapter 24 — Run Young Man!!
• Chapter 23 — The confession
• Chapter 22 — Coward
• Chapter 21 — The Passing Days
• Chapter 20 — Nonoa's Gloomy Day
• Chapter 19 — History's biggest battle plan
• Chapter 18 — It's Show Time
• Chapter 17 — PTM:Peeping Teacher Minowa
• Chapter 16 — Another Observation...
• Chapter 15 — Thin Ice
• Chapter 14 — Coming Out!
• Chapter 13 — Howling Boy!
• Chapter 12 — Looking for the Culprit
• Chapter 11 — A Play Back of That Day
• Chapter 10 — Secret x Secret
• Chapter 9 — Iron Protrusions!
• Chapter 8 — That Girl's Observation
• Chapter 7 — I'm Nonoa
• Chapter 6 — A Close Call
• Chapter 5 — That... Has Come Out
• Chapter 4 — Iron Will
• Chapter 3 — Not Eating What Is Set Before You
• Chapter 2 — Tsukiko's Secret
• Chapter 1 — A girl's "That day"