It is an aggressive word and is usually used when you want the audience to perceive it as a negative action without straight up telling them. In definition, it is harassment, and thus produces an unfavorable effect for those on the receiving end, but the connotation is that the effect is more severe.
"Like sparks from a blacksmith's window" refers to the sparks that happen when a blacksmith is working. The meaning depends on the context. The context should usually be something like anger, exploding anger, or it could be excitement...
“Onomatopoeia” is the figurative language used in this sentence.
Because “sploosh” can be identified as a sound, and onomatopoeia is the formation of a sound to a word, that would be the answer.
