If you are looking for the specific manga associated with this title, it is an adult Doujinshi created by the artist .
If you are asking about the meaning of the character type: ane wa yan
: The series falls into the adult (H-anime) genre and typically revolves around themes of family dynamics and motherhood. If you are looking for the specific manga
But context matters enormously. Depending on the tone and situation, "ane wa yan" can convey surprise, frustration, declaration, or even affectionate teasing. "ane wa yan" can convey surprise