Do you think Goku should have known Vegeta was going to hit him from behind (Buu Saga)? Does this ever come up again?

[Warmmedown]

No homo here

Yeh anyway - when he first meets Trunks he says he didn't dodge because Trunks doesn't have the ki of a killer. Is that because he could only discern between murderous and non-murderous ki? Or is he just like Nail where he can sense "evil ki"? Or can he do both?

Why couldn't he sense Vegeta about to hit him?
Is it because Vegeta wasn't trying to kill him?
Or Vegeta's ki being Majin (already a ki with bad intent, since Vegeta said he chose to go Majin so he could be mean like his old self (paraphrasing)) masked the ill intent.

Does the ability to sense murderous, evil or ill-intentioned ki ever come back again? Are there times Goku or someone else could've sensed actual killing intent in an attack but didn't? Or times that Piccolo-Nail should have sensed that a ki was evil but didn't?

 

[Zippy]

A few things that maybe played a role;
He just got done fighting vegeta so it wouldn't be suprising to sense intent to harm from him anyway.
Vegeta also hit him off guard while trunks attacked him head on
Also there was alot of shit going on he didnt have his entire focus on vegeta alone like the trunks situation.

 

[SSJ2]

Agreed with Zippy. I think it's just Goku's overall naivety and overtrusting nature. Vegeta also wouldn't have had killing intent when he went to knock him out, so perhaps Goku wouldn't have sensed it at all.

 

[Fantastische Hure]

Yeah, killing intent is a thing. I’m not sure how it is sensed or perceived in Japanese but some-how characters can sense “Satsui”.

 

[GreatSaiyaman123]

I think this kind of stuff has to be really blatant to stick out. Freeza was a genocidal maniac, Piccolo was basically a demon. Vegeta was sucker punching Goku for noble intents (sacrificing himself).

Also, Goku is too trusting. He always gives people the benefit of the doubt. Remember how me tried to spare Freeza like, 3x in a row?

 

[Son Gokū]

Uh...I'll admit. That's on me...