SOLYGBM analysis of W.D Gaster! spoilers for chapters 437-439
Gaster starts by acting overly polite and flattering in front of Don Dee. He praises him, encourages him, and uses a friendly tone that feels more like manipulation than sincerity. When Don Dee leaves, this behavior disappears immediately. Sans looks up and sees Gaster narrowing his eyes in irritation, followed by the comment, “You were right, brother. That human does seem to lack manners.” The quick switch shows that the polite act was something he put on only for show.
After this, Sans becomes quiet and avoids talking to him. Gaster notices the change and approaches him with a teasing smile, the type some parents or caretakers use when they decide to treat a serious situation as something small or silly. He says, “Please do not tell me you are still mad about that bar, little brother.” Instead of acknowledging why Sans is upset, Gaster makes the issue sound minor, which minimizes Sans’s emotional reaction.
This is a pattern that appears often with toxic parents or caretakers. Gaster, even when he is speaking truthfully, still frames Sans’s reaction as childish whenever things do not go his way. That is another way to downplay his feelings.
Instead of having a respectful conversation, he leans into teasing that feels more mocking than gentle.
Many parents or caretakers use this same approach. Instead of a firm but fair lecture, they give their comments in a teasing or slightly humiliating tone, knowing they are in the higher position.
The child, or in this case the younger sibling, will rarely talk back because they know the imbalance of power is there.
When Sans finally talks back and curses at him, Gaster’s response is immediate. His tone shifts in a second. He keeps the smile on his face, but his voice becomes noticeably more stern and direct. It carries the feeling of “Do not do that again.” This kind of sudden seriousness can be jarring, especially given the calm or joking tone he used just moments earlier.
But then, just as quickly, Gaster switches again. He turns cheerful, saying things like “We have a reputation to uphold!” as though nothing threatening came out of him a moment earlier. He moves on quickly, without giving Sans any time to understand or process that shift in attitude.
These tone changes can look playful from the outside, almost like he is trying to act like the “fun older brother” who teases his sibling. But for Sans, who remembers how Gaster behaved in the past during arguments or punishments, these sudden shifts can be uncomfortable and even unsettling. That stern tone he slips into is familiar in a negative way. It is the same tone he used when scolding or arguing with Sans and Papyrus as children. Because of that, even mild teasing mixed with those sudden shifts can feel tense or unsafe.
And finally, when Sans started ranting about how angry he was that Gaster blew up Grillby’s bar and how he now had to walk all the way to Hotland just to get a decent drink, Gaster’s whole expression changed. All the light he had in his eyes and attitude disappeared, and he glared down at Sans.
The threatening tone he used earlier, when he warned Sans not to curse, now made sense as a small warning of what was coming.
Gaster had pushed him around, teasing him even though he knew Sans had a short temper. But to him it didint matter, cause he already forgot about the entire Grillby situation, and beacuse of that he automatically gave himself the permission to joke about it so freely.
Because Gaster had already forgotten about the situation, or simply did not care as much as Sans did, he continued to tease him.
To Gaster, it was something small enough to joke about or move past quickly, so he treated it like a joke without considering Sans’s perspective. Since Gaster himself had let it go and did not see it as important anymore, he assumed it was appropriate to make fun of it, not realizing or not caring how serious it was to Sans.
This mirrors how many parents or caretakers behave when they forget or downplay a situation that mattered to the child.
They do not care about how important it felt to the child, and they become irritated when the child does not “move on” as quickly as they want them to, or as quickly as they did.
This causes frustration and snapping, just like in Gaster’s case, where he becomes annoyed and offended after provoking the reaction himself.
