My suspicions about Leon turning to be the culprit were nailed right based upon the scribbled message the deceased Sayaka left.
However, I employed a method a little bit long winded than the simplistic explanation Naegi offered to decipher the message.
11037
The '3' digit was inscribed in such a manner that resembled a reversed 'E' in leet. Of course, I also mentally turned upside-down the whole number in order to read it as "LEON".
As for the extra seat reserved for the graduate, I do not buy MonoBear's explanation. Furthermore, I do not believe at all that extra seat is put there just for decoration or to bestow honors.
Recall MonoBear's creepy prologue at the very start of the first episode, and remember also that MonoBear wants the teens to go pure despair?
Spoiler:
Both my hunch and common sense are telling me that extra seat is reserved to punish the one whom is left standing at the end for graduation.
- The rules are that in order to graduate one must kill all the other enrolled students without being found out.
However, what is there a subtle paradox of sorts in that rule.
- At the classroom trials, if the accusers nailed right the accused being the true culprit, the accused gets executed for disturbing the rules.
- On the other hand, if the accusers got it all wrong about the accused being the culprit, then the accusers get executed for defamation which is also against the rules.
Now, my proposed paradox of sorts is:
- The culprit manages to murder every last contestant and gets to graduate.
- Paradox: Even if the rules say that the culprit can graduate, he or she still gets executed due to committing murders and disturbing the rules.
After all, MonoBear's the one who came up with the rules, and it can enforce them in anway that pleases it.
- This paradox seems apt to me, since in the long run would play with MonoBear's constant theme of playing with the students until every one of them collapse from despair.