What about the scene in Speak Memory in which Nabokov was forced to sit on Uncle Ruka's lap, the uncle petting him and lavishing on him endearments until N's Father would put an end to these embarrassing episodes? Don't these have some connection to the famous scene involving Humbert's relieving himself with Lolita's legs on the Haze Davenport sofa? By the way is a similar scene to both in The Defense in which the demented chess genius has an orgasm while being touched by the woman he marries without her understanding what's happened.