- "Aitsu", "Koitsu", "Soitsu" and "Doitsu" are from Sexy Parodius, a Konami game that parodies Gradius.
- When translated, the names "Koitsu", "Soitsu", "Aitsu" and "Doitsu" mean "This Guy", "That Guy", "That Other Guy" and "Which Guy?" respectively. The names are whimsical, and are not meant to be taken literally. To keep the flavor, an appropriate translation might be "Eeney", "Meeney", "Miney", and "Moe".
- "Aitsu" is featured on the artwork of the following cards:
- "Aitsu" and "Koitsu" make an appearance in Konami's Castlevania: Harmony of Despair when a player controlling the character Jonathan Morris uses the subweapon, "Paper Airplane" at a higher level. At level 5-8, only one person can be seen riding the airplane. But at max level (9) both "Aitsu" and "Koitsu" can be seen riding on the plane.
- They also appear in Castlevania: Portrait of Ruin when the player has mastered Johnathan Morris's Paper Airplane subweapon. They will either appear individually or together on the plane when the player uses it.