Summary
It’s well known that Hollows inBleachoften used to be human souls who were corrupted somehow after death, often by their attachments to the world of the living. However, this fact about Hollows was originally used to justify using a very particular technique to slay them–a technique which the story quickly abandoned, even though it had a lot of potential for drama.
InBleach, Hollows are monstrous beings which devour humans and other soul beings, such as Soul Reapers. They wear masks over their faces which are made from the hearts they once had. While not all Hollows were originally human, the overwhelming majority of them–particularly those active in the world of the living–were. As former humans, it’s easy to feel some sympathy for those who’ve fallen into this terrible fate.

This is never more relevant than it is in chapter 3 of the manga, when one such Hollow that has been focused on Orihime is revealed to have once been her brother, Sora.
Bleach’s Hollows Could’ve Been Emotionally Devastating
The Reveal of a Hollow’s Former Identity as a Human is Underutilized
In chapter 3,Rukia states that it’s importantto always kill Hollows with a strike from behind, something which Ichigo initially scoffs at, feeling it’s unsporting to attack even a monster from the back. However, Rukia is very insistent, and eventually the circumstances force her to reveal why:Soul Reapers are told to always kill Hollows from behind so that there’s no chance that they see the Hollow’s formerly human face underneath the mask.Seeing the human face could cause a Soul Reaper to hesitate or feel sympathy for the monster, potentially putting their life at risk.
This is used to great effect with the reveal that the Hollow following Orihime is in fact her deceased older brother, as Ichigo goes against Rukia’s advice and does indeed see Sora’s face. The fact that this monster is someone that Ichigo is familiar with on some level does affect his ability to fight against it, proving Rukia had a point, even if it’s somewhat cold-hearted advice. However, while this reveal is played for all the drama it can offer, this fact of fighting Hollows never really comes up again, and it’s a shame, as this added a complex dynamic to battling Hollows.
The need to kill Hollows from behind is somewhat akin to the Titans fromAttack on Titan, who can only be killed when struck in a very specific spot on the back of the neck. That series obviously made great use of the difficulty of only being able to take down an opponent from behind, showing how it can add complexity to battle scenes. Hollows could even perhaps attempt to take advantage of a Soul Reaper’s feelings by removing their own mask, forcing their opponents to acknowledge they’re going up against a former human. It would be even more interesting to see how this applied toadvanced Hollows, such as the Arrancar, which are already very human-like.
While the series is perfectly enjoyable as-is, the fact that this quality of a battle with a Hollow was so quickly forgotten is still disappointing, as it had so much more potential to inject additional drama intoBleach.