This work depicts the clarinet player Rin, a member of a certain famous orchestra, spending 30 days mastering the art of anal sex. Despite Rin's petite and serious appearance, the content is unexpectedly extreme. Starting from the basics, it portrays the progression of skills in a manner reminiscent of a music professional honing their playing technique. It also includes extreme depictions such as a 50cm dildo, a huge penis, and intense fisting, all leading to the powerful evolution of Rin's monstrous anus. Furthermore, the scene featuring a C# harmonic scream is displayed without mosaic, highlighting the realistic portrayal. With the blossoming of masochistic talents, the climax of joy is played out in a symphony of being plugged in three holes. The magnificent anal orifice is truly worth seeing.