It is the meaning of life... it is... life itself. Or ya' know just a meme/class the "Semi-Class" is The Sandvich, The Holiday Punch, and The Officer's Ushanka. The meme is from the line that the Heavy can say "Put dispenser here." But due to is RUSSIAN accent it sounds like he says "Pootispencer here!" Making a meme that turned into a "Semi-Class."
The very top of your butt crack, where it is just a fold and does not lead to anything, such as a butt hole. Often times, when somebodies buttcrack is showing, it is the pootis.