After telling us about Maria and the fizz powder, Oskar decides from inside the asylum that he needs to get more of the stuff. He asks his keeper Bruno to find some, but all of Bruno's efforts come up short.
Bruno's able to get one of the institution's chemists to make up something that's about the same.
The next time Maria visits, Oskar shows her the powder and puts it in her hand. She's very embarrassed by it, though, and asks him not to talk about it. She claims to not even remember it.
Apparently, the memory of sharing a bed isn't as fond for her as it is for Oskar. Uh, ya think?
Instead, Maria turns the conversation to her son, little Kurt Matzerath. Oskar's all but certain that he's this boy's biological father.
About ten days after Oskar assaulted Maria while she was asleep, he found Maria having sex with his father Alfred in the family kitchen.
Oskar can't believe his eyes. He runs toward the two of them and starts hitting them both.
Soon after, Alfred decides to marry Maria, who's only seventeen. She's pregnant, and Oskar is furious that the child he thinks is his will be raised as Alfred's for the sake of respectability.
A few months later, Maria gives birth to Kurt Matzerath.
Oskar returns to the moment he attacked Alfred and Maria while they were having sex.
He says that Alfred struck him to knock him off. Maria takes Oskar under her wing and tells Alfred not to hit him.
After Alfred storms out, Oskar's alone with a half-naked Maria. As she gets dressed, Oskar can hear special reports from the German army coming in over the radio.
Maria leaves the room to go wash up, while Oskar stays behind and drums. Maria eventually comes back and sings part of the song that he's drumming.
After that, a silence falls between them. Maria's obviously upset about something.
To cheer her up, Oskar sneaks into the family grocery store, grabs a packet of fizz powder, and brings it back to her. She stares and doesn't respond, so Oskar tries a more direct route. He takes her hand, pours some of the powder into it, and then spits into it.
Before the stuff even starts to foam, Maria sends him flying across the room with a hard kick to the chest.
Oskar's back to his feet in a second. Maria wipes her hand off with a towel and calls Oskar a filthy little dwarf.
She grabs him, slaps him, and stuffs the towel in his mouth when he's about to scream and shatter all the glass in the house.
When Oskar seems to calm down, Maria laughs and tries to make up. But Oskar isn't done yet. He hits her between the legs with an uppercut and keeps attacking her until Maria's crying with pain and Oskar's crying from what's probably a combo of injured pride and heartbreak.