Overall is good.
Gameplay wise. Is pretty simple. You move either left or right, hold x to aim your weapon, whenever it is a spear or firearm, and hit z to stab or shoot. From that point on, just reach the end with that controls. Enemies can hit you sometimes until you fall, where they grab you into a h-cg. Otherwise, you can hold z to provoke enemies, and make it so they don't hit you, instead they go directly to grab.
That is about it when it comes to gameplay, I would not say is bad, is just simple (except for the baby spiders. Not being able to hit them with melee, and having to wait for them to jump, is bullshit)
Story wise is also simple. An outbreak and you have to escape.
Art wise is quite good. There are the cgs which I really liked, and some of them have interactions with monsters of the same kind, like 2 male zombies or 2 females zombies. When it comes to pixel art, these are quite well-made.
Additionally, there is the game over scene which is an animation, giving it points obviously since usually is not done.
My only complaints (aside from the baby spiders one) is that 1 they are censored. It is not heavy censored, is the usually badly done squares, and even while using the C 0 trick, in dev console I could not get it off. And 2, the final fight is boring, like the moment you understand how to aim and shoot, is just a repetitive cycle till you reach the end of the tunnel.
I would say it is a solid 9/10, pretty short, about 1 ~ 2 hrs depending on how much you rush.
There is no 4.5, so I am rounding up.