Do-S

"Monster Princess" Do-S (怪人姫弩S, Kaijin Hime Do S; Viz: Monster Princess Super S) is a Demon-level Mysterious Being and a member of the Monster Association.

Appearance
Do-S is a monster that resembles a human female with long blonde hair with a black flower on the left side of her head. Her eyes are light with black sclera and has a pink heart-shaped symbol on her forehead as well as many piercings on both ears. She dresses in a BDSM outfit made of straps and held by metal rings revealing her fit and voluptuous figure. She tops her attire with high heeled boots ripped by the side and ripped arm warmers. She also dons her outfit with a spiked choker.

Personality
Like her appearance and attire suggests, Do-S acts in a similar manner to that of a sadistic dominatrix and princess like whipping at her opponents and expecting them to follow her orders to the letter. She also likes to toy with opponents she finds amusing like Fubuki and suggests on using her against Tatsumaki. When injured enough in a fight, she abandons her dominatrix persona and becomes a ruthless fighter intent on destroying her opponent though is prevented from doing so and would even flee for her life if faced with one she knows to be far stronger then she could handle like Tatsumaki.

Monster Raid Arc
Do-S appears along with the other monsters of the Monster Association simultaneously attacking a random city. She easily defeats Darkness Blade, Saturn Man and Pandaman and explains her abilities to Dynamite Man. She then orders the now hypnotized heroes to attack Dynamite Man, but they are immobilized by the Blizzard Group. Before she is able to retaliate against them, Fubuki stops her whip in mid-air.

Do-S was overpowering Fubuki and managed to turn all of Fubuki's subordinates into love slaves. While Fubuki tries to hold off Do-S's love slaves, Do-S's whip eventually manages to pierce through Fubuki's telekinesis and hit Fubuki. Do-S manages to hit Fubuki multiple times. Believing that she has Fubuki's mind under her control, Do-S approaches Fubuki and tells the hero about her plans to lure Tatsumaki out. Enraged, Fubuki sends Do-S flying back. Before Do-S could get a hold of the situation, Fubuki uses Hell Storm, which slightly injures Do-S. As it turns out Fubuki did not succumb to the monster's mind control. Do-S changes her plans and decides to kill Fubuki instead of using the hero to lure Tatsumaki out. Fubuki tells Do-S that her sister would come anyway.

Tatsumaki causes an explosion in the city where Do-S and Fubuki are fighting. Do-S realizes the mistake she has made and immediately tries to make an escape plan. A monster falls in front of Do-S asking for help and warns her of Tatsumaki. Tatsumaki finally arrives and immediately tells Fubuki to go home and that she will handle the rest. Do-S orders to her love slaves to attack Tatsumaki as a distraction as she escapes. Tatsumaki immobilizes all of the love slaves, but Do-S manages to escape.

Monster Association Arc
Back in Monster Association Headquarter where Orochi executes Awakened Cockroach by devouring him mercilessly due to the latter's failure on defeating Genos, Do-S was about to be executed. Thankfully, she is spared on behalf of Gyoro Gyoro's request to Orochi.

Abilities and Powers
As a Demon-level Mysterious Being of the Monster Association, Do-S is an extremely powerful being. She was able to give Fubuki a tough fight, albeit by splitting her focus.

Supernatural Abilities
Mind Manipulation: Do-S possesses the ability to control the minds of others. She achieves this by hitting them with her whip. Those who are controlled by her, have heart-shaped pupils and are referred as her "love slaves". However, people with strong willpower can resist this power.

Physical Abilities
Enhanced Strength: Do-S possesses the raw power to send several people flying with just a crack of her whip. Her whip attacks were noted to be very heavy by Fubuki. Her whip attack eventually pierced through Fubuki's telekinesis when Fubuki was holding off Do-S's love slaves.

Immense Durability: Do-S is capable of withstanding the attacks of Fubuki, while only gaining several scratches.

Enhanced Speed: Do-S is able to escape Tatsumaki after using her love slaves as a distraction.

Fighting Style
Expert Whip Specialist: Do-S has shown great skill with her whip in combat. She is able to dish out multiple hits with just a single crack of her whip. Do-S uses hypnosis in unison with her whip in combat.
 * Heart ♡ Hard ♡ Hit (ハート♡ハード♡ヒツト, Hāto ♡ Hādo ♡ Hitto): Do-S cracks her whip, sending out multiple slashes at once. This attack is capable of knocking multiple people back many meters. Those who are hit by this attack become her love slaves, which she can control freely and make them usually do her bidding. Despite that, this power is not applied to a strong-willed person.

Equipment
Spiked Whip: Do-S wields a spiked whip that turns victims struck by it into love slaves, who are people that will blindly serve Do-S until they die, with a special stimulus.

Trivia

 * The "Do" in Do-S' name is written as 弩, which means "crossbow". "Do-S" literally means "Big Sadist".