Gengè is the name Dida calls her husband, Vitangelo Moscarda, from the first pages, and it is also the man she built and loves, with thoughts, feelings and tastes that are not his. In the novel, the affectionate nickname becomes the central figure of the thesis: the husband Dida sees is not Moscarda, but a puppet she made.
In Book I, Dida calls him Gengè every minute, with the news of the house, and Moscarda only understands the nickname at the end of the book. In Chapter XII of Book II he recognizes the truth: she knew her Gengè better than he did, because she built him, and the Gengè was not a puppet, the puppet was he. Dida neither subdues nor replaces him, because to subdue someone that someone has to exist, and for her the husband did not exist.
The hairstyle proves the love. Dida undoes the girlish hairstyle that pleased them both because she thinks it pleases the Gengè more this way, and Moscarda is jealous of a fool who has come between him and his wife. In Book V he tries to break free: he shouts that the Gengè is not him and that this marionette has had enough. In Book VI, his father-in-law, the daughter and the bank's partners reveal themselves comfortable with this puppet, which is why the father-in-law flees shouting "madman!" when Moscarda threatens to take him out of that condition.
Gengè is, in the end, the name of the image one person gives another and that the other cannot correct. Dida is sincere in loving him, and that is the deadlock of the marriage.