An idea I had is that Syahata could come across a laboratory or some science building. The bulding would have some slime like monster and zombies just like the school ( The zombies would be science related ).
The zombies would be just like the ones at the school just a bit stronger and faster
The slime monster would be just like the one in the sewers but it would absorb Syahata. The slime would dissolve her clothes.
The slime would split in to smaller slime once killed. The small slime could regroup to be a normal slime or attack her. The small slime could slow her down if it were to attack her
( One small slime could be on her feet slowing her down by 10% )
( Two small slimes could go up her legs and into her skirt, She would be slowed by 25% )
( Three slimes would just knock her down and she would need to get them all off or it could be a se❌ scene)
You can remover the slimes by
.using a melee attack
.having a new control
.having some sort of decontamination place in the building