負っけないぞ~! ふぬぬぬぬ……
Is it the same as "ぬぬぬ…" onomatopoeia which uses when you're in a tight spot?
負っけないぞ~! ふぬぬぬぬ……
Is it the same as "ぬぬぬ…" onomatopoeia which uses when you're in a tight spot?
負っけないぞ~! ふぬぬぬぬ……
It's a variant of "ぬぬぬ…". These similar onomatopoeiae (or voices)「ぬぬぬ...」「ふぬぬ...」「うぬぬ...」「ぐぬぬ...」 etc. can be used for describing the state of being angry (怒っているとき), doing something very hard (がんばっているとき), straining yourself ([力]{りき}んでいるとき), standing hard (ふんばっているとき), or suffering / feeling pain (苦しんでいるとき), as well as being in a tight spot (困っているとき).