Sweetheart's cruel and merciless archenemy and corruptor of all things pure. Bitterbat loves bringing chaos to a good day. If not for the fact he has never taken a human life, Bitterbat would be the most dangerous villain. Instead, he remains in the top 5.

In reality, Bitterbat dislikes the idea of killing innocent people (thought maiming isn't entirely out of the question if needed) and just wants to spend as much time as he can with his girlfriend, Sweetheart. However, that's difficult when she's constantly trying to keep the city falling apart due to what better a solution than to become the villainy she constantly has to stop? When Bitterbat isn't off somewhere unleashing monsters on the city, he is back home at Sweetheart's apartment being a good house husband in training.


Mischievous, sly, yet dense and one track minded. Bitterbat, just like Sweetheart, is an amazing actor and can switch between his evil persona and true personality in the blink of an eye. The transition is so seamless sometimes that it's hard to tell when he is truly acting and when he is being genuine. Even Sweetheart struggles sometimes...

...until he starts to gush about her. Which happens frequently as he is the most love sick creature on this side of the universe. He has his whole future planned with Sweetheart and is always willing to share it to a lending ear. The one thing that never fails to make him show his true colors is when Sweetheart is threatened by anyone. He doesn't discriminate between allies or enemies as the only thing that matters to him is his Sweetie Pie.

Anyone that tries to come between them is an obstacle he won't hesitate to eliminate.


Bitterbat doesn't like to talk much about his past, even with Sweetheart. What is known is that he met her during her middle school days and has been lovestruck ever since. After the defeat of his father, Lord Vile, the link between Earth and his home dimension, Marianus, was broken and he was stuck on the other side of the portal for nearly 3 years. During those 3 years, he worked on cleaning up the mess his ex-boss left behind while preparing for the day he eventually reunited with his Sweetie. Thanks to Red-Hot, Sourpuss, and Halite, a portal was fixed and he could return to Earth eventually.

What was planned was reuniting with Sweetheart. What wasn't planned was a mutual confession leading to a one night stand...not that he's complaining. However, he certainly had to tinker with his originally blueprint as dating meant he had to also balance his villainous image with his relationship with Sweetheart.

Things got a bit more complicated once Red-Hot, Sourpuss, and Halite found their way to Earth as well as that meant the link had been repaired.

And door often open both ways.

Skills and Abilities

Bitterbat is incredibly flexible with alarmingly fast reflexes and a good grasp of magic. Bitterbat is also an amalgamation of various living creatures. One of such being an incubus. Thankfully, it's such a low percent, it doesn't alter his daily life aside from him getting an additional boost of energy when he comes into physical contact with Sweetheart.

The Bitterbat
A double-bladed staff that he can change into a bladed and spiked hoop.

Limiter Spikes

Bitterbat is incredibly strong. It's almost to a concerning amount, which is why he wears limiters (spiked collar, bracelets, anklets) so people actually have some sort of fighting chance against him. The spikes are actually pins that puncture his skin and in lack of better terms, pin down his power to a more reasonable amount.

He can control how many pins are puncturing him at a time, allowing him to uncap a bit more power with his monster monarch form being the only time all his pins are fully released

Monstrum Abilities

All Monstrums have an element tied to them that shapes the magic they use. Bitterbat's is fear

Soul Suit
A marking shared with Sweetheart that symbolizes Bitterbat's love for her. It's an official sign of them being mates and allows them to sense the other's emotions. Due to Bitterbat being an Alpha Monstrum, his soul suit comes with the added effect of all lower ranking monsters becoming subjects to Sweetheart, often bowing to her and listening to her orders.

Monster Mania
Although Bitterbat isn't a Beloved, he shares the same love based power. His specific love is Mania, better known as Obsessive Love.

He channels this by thinking about his one true love, Sweetheart. This adds a crazy amount of power to his already high power level, resulting in Sweetheart ironically being the only hero in the city who can and could stop him if he truly did go full evil.

Bitterbat has toxins in his body he can channel and inject with his fangs, claws, or scorpion tail. He can decide how lethal of a dosage he injects with the highest dose being able to kill a target within seconds.

Monster Forms

Due to being an Alpha Monstrum, Bitterbat a total of three forms he can turn into while most other lower ranked Monstrum only have two.

  • Mini Monster: A pocket-sized monster form Monstrums can take. It's usually used for quick escapes in battle but the Flavor Four have repurposed it to have some fluffy times with their Beloveds.
  • Bitterbeast: A "medium" sized form. Similar to the mini monster, Bitterbat can shift into this form by free will. It allows him to use a bit more power without reaching his safety cap.
  • Monster Monarch: A large monstrous form only Bitterbat is capable of transforming into due to his high ranking. It's the most destructive form due to him releasing all his limiter spikes. Sometimes, Bitterbat transforms into this by total accident due to him being a Monstrum of emotions...specifically love.


  • Bitterbat's name is a play on the phrase "Pitter-pat" as reference to a rapid heartbeat aka a common sound for him when he's around Sweetheart.
  • Bitterbat's civilian name, Ace, name comes from the playing card "Ace of Spades" due to the spades marking on his chest. With it often being the highest ranked card in a deck, it made sense to name the future king of monsters it.
  • Even though Bitterbat has a small percentage of incubus in him, physical contact from any random person has no effect on him. It has to be a lover. In his case, he needs that physical lovin' from Sweetheart.
  • Bitterbat celebrates Sweetheart and his anniversary the 16th of every month.
  • Bitterbat wants 12 kids in the future so he can celebrate a birthday every month. And due to Monstrums being "built different", he is fully capable of carrying children himself
  • Ironically, Bitterbat tends to struggle with other people's children.
  • Bitterbat binges cooking videos in his free time so he cook meals for Sweetheart.
  • Bitterbat enjoys watching DIYs for various things (chores, cheatcodes, etc.) so he can be the best husband ever.
  • Bitterbat got his ears pierced by Red-Hot when he was a kid to mirror Sweetheart.
  • Bitterbat tends to hold hands with Sweetheart when he sleeps out of fear he will drift away from her and wake up back in his home dimension.