Misae Ikari may be the weakest character in the show physically, but she basically tells Lil' Slugger "screw you".
When she starts the conversation, she tells him to sit down and listen. He sits down and listens.
During the talk, he tries several times to pick his bat back up. He fails several times, as if just being near her makes it difficult to lift it.
Then he starts to grow to an immense size. He swings his bat at her, hard enough that her hair is blown back. She doesn't even look up.
Then he starts trashing the room since he can't get to her. And when he finally does manage to score a glancing blow? She pretends to be frightened just to lead him on, and then laughs in his face. Yes, she actually Trolls Lil' Slugger.
In her last appearance, she manages to break into her husband's Lotus-Eater Machinetwice, despite Masumi's attempts to keep her out, and tells him goodbye and that she loves him, before she dies. This is enough to remind Ikari of what he told her about hiding from reality, prompting the scene quoted below, in which...
...Chief Ikari, prompted by his acceptance of his beloved wife's death, breaks out of the Lotus-Eater Machine.
Ikari:...Since when was I ever your father? ...I get it now ...It's all starting to make sense. This whole place is nothing but a big lie! It's all just a lie! Everything! I'm surrounded by fools and idiots!
Maromi: Wait! Stop it! This is your world! You have a place here!
Ikari: Stop your babbling, you stupid dog! My place disappeared from this world a long time ago! The reality is that there is no place for me anymore—but that's the reality I have to face!
Hirukawa, wandering the streets while in the Despair Event Horizon, gets attacked by Lil' Slugger. However, unlike everyone else that fell victim to him, Hirukawa isn't knocked unconscious, and he immediately berates Lil' Slugger and knocks him down with a shoe before giving a No-Holds-Barred Beatdown. Unfortunately, it wasn't the real Lil' Slugger, but he gets points for trying.
Episode 10's climax. While not as detestable as Hirukawa, the production manager's habit of screwing things up for the rest of the anime production staff while thoroughly refusing to so much as apologize for his own ignorance - to the point where he snaps and starts killing at least some of them under the guise of Lil' Slugger - means that his eventual doom at the hands of Lil' Slugger is rather deserved.
Maniwa fighting Lil' Slugger as the Radar Man - and standing a chance against him. He's also the one who recovers the Backstory of Maromi and Lil' Slugger.
("Kingdom", by Susumu Hirasawa), is incredible.