Typical msize "lesson" videos include:
You cannot fix what you cannot measure. The first week of the lesson involves no practice. Instead, you must record your current performance. Are you hitting 60% of your shots? Do you make a specific typo 30% of the time? The Msize Audit identifies the "medium difficulty" tasks—the things you succeed at sometimes, but not always. These are the "Msize Gaps."
So "msize ikisugi m lesson" likely refers to a specific adult video series or title from the msize studio featuring intense orgasm/ejaculation scenes with masochistic roleplay.
Even with the keyword in hand, many practitioners fail. Avoid these pitfalls: