Shrieker

is a Hollow with features resembling a bat and a frog. He was the fourth Hollow to be defeated by Ichigo Kurosaki, and the second to reveal his history.

History
About 4 or 5 years ago before the main storyline, Shrieker was once a serial killer, that killed 7 or 8 people. He roamed around various places killing people, preferably women, using what looked like a butcher knife. Yūichi Shibata's mother was his last victim. He stabbed her multiple times while she protected her son, eventually following her out to the veranda. As he was about to stab her for the last time Yūichi grabbed onto his shoelaces, making him lose his balance and subsequently falling out of a high story window. This event led to Shrieker's death as a human, but also his inevitable transformation into a Hollow, still holding a grudge against Yūichi for killing him.

Agent of the Shinigami Arc
Shrieker decided to play a game with Yūichi, taking his soul out of his body, and placing it inside a parakeet. He told the boy that if he could run away from the Hollow in his current form for 3 months, Shrieker would restore his mother to life. Of course no Hollow or other creature can restore life to someone that has died, as Shrieker only started this game to gain more victims. Attempting to save the boy's soul, two Shinigami were already eaten by Shrieker before he met Ichigo. Eventually the bird storing Yūichi's soul comes into Yasutora Sado's ownership. Shrieker injures Chad while he is protecting the bird; because of this, he comes into conflict with Rukia Kuchiki. Rukia teams up with Chad against him, but just when it seems like he would be defeated, Shrieker gains the upper hand thanks to his abilities. He enjoys chasing Rukia around, all the while injuring her until Ichigo Kurosaki takes over the fight. Shrieker tells Ichigo his story, and laments how he was unable to kill his victim's child before death. Ichigo then defeats the Hollow, cutting his head in two. However, unlike most Hollow that are purified of all sins upon purification, Shrieker committed great sins as a human before becoming a Hollow; this is why instead of being purified completely, Shrieker's soul is sent to [Hell].

Powers and Abilities


Artillery: Shrieker can control little creatures he describes as his "artillery." At first glance they seem like miniature Hollow, but they are merely creations from Shrieker's own body like secretions. They cannot feel pain and have a little willpower, not nearly enough to do anything though. These creatures are Shrieker's primary weapon against his opponents, and can hold someone of Rukia's strength down(while in her Gigai.) The creatures can also shoot leeches out of their heads that attach to anything they hit.

Explosive Leeches: By vibrating his tuning fork-shaped tongue, Shrieker can make the leeches his artillery fire explode. Since the leeches reside inside of the creatures Shrieker creates, when using his tongue's vibrations the creatures can also explode, but only upon being cut.

Flight: Using his wings Shrieker can fly in order to escape enemies, staying just out of reach, or to gain the advantage by shooting artillery from afar. This ability explains why he was able to travel so easily in search of the parakeet, and probably made it easier for him to kill the two shinigami.

Trivia

 * When Rukia attempts to pay for her items at Urahara Shop through bounty rewards, Shrieker has a bounty reward of 5000.
 * Shrieker is the only spiritual being seen so far to retain his personality completely after turning into a Hollow, as well as the only one to be sent to Hell.