These are the notes found at the beginning of Sensei no Ojikan 04:

- <b>Brada</b> is a small parody of the famous designer brand, Prada.
- An <b>obi</b> is a sash that goes around a kimono or a yukata.
- <b>Geta</b> are Japanese wooden sandals with two flat bottoms that would be very painful if used to step on someone's feet.
- When added to a name, the suffix <b>sama</b> is an honorable way to address someone. In the case of "Ojou", sama is added to give the female a much higher status.
- In Japanese, <b>Romance of the Three Kingdoms</b>, <b>science fiction</b>, and <b>Salaryman Senryuu</b> all start with the Japanese syllable <b>'Sa'</b>. When Oyaji begins to say Science fiction, Mika assumes he means Romance of the Three Kingdoms. So instead, Oyaji covers by saying he bought a Salaryman Senryuu.
- <b>Senryuu</b> are comical haikus that mock various aspects of life.
- <b>Natsu-comi</b> is the abbreviation for the Summer Comic Market, the biggest doujinshi convention in Japan, which in recent years has also featured cosplay and commercial booths where companies sell spin-off products of their titles. The Comic Market is held twice every year, in the summer and in the winter. The summer one surpasses the winter one in attendance, traffic congestion and horrible smell from the hordes of unwashed, sweaty otaku.
- Towards the end of episode 4, Suetake bangs a pan with a mallet that makes a clanging sound, which is represented with the Japanese katakana <b>‘kin.’</b> Afterwards, Kudo yells <b>‘Tamaya.’</b> After combining and manipulating these two phrases, you get ‘kintama... ya’, which in Japanese slang pretty much means, ‘Yay for testicles!’