Yo, my friend. :D So this is the last part of your review thingy. I hope you enjoy! 

Changed: Once all of the bottle, containers, and canisters were filled to the brim with fresh water and shut tightly, Yukwon led the way to the helicopter through the green brush.

Reason: I added the comma there because that sentence would be quite a mouthful if the commas weren't there to save your breath. After your second comma, the sentence just stretches long and has two ideas just going straight in one shot. 

Changed: "We're on a deadline, the copter is waiting,' Yukwon kindly reminded. If I had said that, a string of curses would've followed. It's good he said that quickly.

Reason: I've seperated 'Yukwon kindly reminded' and 'If I had said that' to two seperate sentences because... A longer pause would just make more sense, don't you think? 

Changed: talking mark/comma/full stop thingy. 

Changed: talking mark/comma/full stop thingy + It's wasn't always nice to be out of uniform; the shirts hugs us a bit too tightly and I don't like the pants. 

Reason: I've added the wasn't because you were describing the negatives of the uniform: too tight and personal tastes. I've also put the semicolon because the are two quite different ideas. 

Changed: I was surprised Yukwon came in only a black tank and jeans; usually Demons are rarely seen out of their uniforms if they're not assigned to an Angel. 

Reason: Since those two are different ideas, I've seperated them with a semicolon instead of the comma. 

Changed: Jiyong rubbed teh back of his hand against his lip; it was probably numb. 

Reason: These two are also different ideas: action and reason. 

Changed: ...running, stopping in my tracks to see the dark haired, kitten-faced Yukwon with a spear twisting around his fingers coolly and two bleeding bodies on the ground.

Reason: When you're listing things, you seperate the things with commas. For example: eggs, blue paint, buckets, and unicorns. If the commas weren't there, it would look like: eggs blue paint buckets and unicorns. Isn't it confusing where the blue paint and buckets are? You wouldn't know if it was just blue paint and a bucket, or a blue paint bucket. 

Changed: ...rustling footsteps. It was dead silent. I picked up my pace a little bit. When I heard a raspy battle cry, I full on sprinted. 

Reason: During this bit, it seemed high tension and you were making the sentences short and snappy. So I tried to make your sentences even shorter to give a bigger effect. I think I've explained in an earlier blog post that shorter sentences give a bigger impact on certain genres such as horror, action, etc.. 

Changed: ... every pulsing body part: your chest, your ears, your wrists, your stomach, your feet, things like that. 

Reason: Must've been a typo, right? ^^ 

Changed: I hit the target. Before Tablo become a douche, he taught me how the mind worked and I used it to be a prick.

Reason: Since you were writing in past tense, you need to turn 'use' into 'used'. 

Changed: talking/comma/full stop. 

Changed: I shouted and hooked Jiyoung in the jaw, making him snort/groan/...? again. 

Reason: ... Being so smart, I didn't screen shot the first part of this and I didn't know what he did the first time. But someone snoring when they get hit is a bit... weird so yea. 

Changed: The rich orange colour had always calmed me down; sometimes Bom and I would sit on our roof and watch the sun either rise or set while trying to stay about the ground. 

Reason: As you know about the semicolon, two different ideas are seperated with it. 

Changed: As if they cared about me, but I almost forgot my promise to myself. 

Reason: I think it was just a typo with 'me' and 'my', and a little tense confusion with 'forget' and 'forgot' 

Changed: Jiyong complained like a baby; if he thought that was cute, he's being stupid! 

Reason: As you already know, two different ideas... 

Changed: "Arreso," they moaned in reply and I pulled out a granola bar, chomping on it eargerly. I needed sugar; sugar helps you and it energizes you to keep walking. 

Reason: First... I'm not sure if I'm right but I think you meant 'arasseo' instead of 'arreso'. I've quickly googled it and put it on google translate and it came out as 알았어 with al--eo as the romanisation. I assume 'l' to be similar to 'r' in sound because I haven't seen 'alasseo' written anywhere.   

Anyway, the other mistakes are just the talking/comma/full stop thing and the semicolon. 

Changed: talking/comma/full stop 

Reason: ... there really isn't a reason thing to put here since you know what I'm talking about but... I would like to take this moment to fangirl over 'Special D.A'. In Harry Potter, Dumbledore's Army was called D.A for short so... Special Dumbledore's Army! ioghaioghaeioghaeioghaeioghaeiogaioea. /spazz/ 

Reason: I think the brackets in this paragraph is quite un-needed. '... and I easily tossed the other blonde...' is enough to give the audience some detail to visualise. Also, '... as I watched his limp body fall onto the ground, someone leaped onto my back...' is enough. 'Limp' tells the audience enough to visualise a floppy body just flop onto the ground. The brackets there just break the flow of it in the middle of all the action.