WARNING: The following contains spoilers for Fena: Pirate Princess Episode 11, "At Mission's End," now streaming on Crunchyroll and Adult Swim.
In Fena: Pirate Princess, Abel, the dashing navy officer, was initially portrayed as a mysterious character who was determined to find Fena. It's revealed in Episode 9 that the woman in the painting is someone he has been in love with and has been seeking for years. Abel has proven to be ruthless in his pursuits and when he finally is reunited with Helena in Episode 11, he's happy and finally at peace before he dies. But given what he has done thus far, does he deserve this happy ending?
In Episode 11 of Fena: Pirate Princess, Abel is more demon than human. His eyes glow red like someone has taken over his body and when his arm gets chopped off by Yukimaru, the wound looks more like fire. When Abel arrives at Eden and catches Fena and Yukimaru together, he doesn't see the two of them for who they are: he sees Helena and Franz. When Yukimaru stands in front of Fena to protect her, what Abel sees is Franz acting as a barrier to him finally reuniting with Helena. It's only when Fena stands in front of Abel to block him from killing Yukimaru that seems to wake him up. Now he doesn't see her as Helena anymore because, in his mind, Helena would never do this.
From that point on, however, Abel sees Fena as an obstacle to Helena as well, proclaiming the princess is no longer useful to him. He has never cared about her despite the fact that she's Helena's daughter, and is ready to kill both Fena and Yukimaru.
In a deus ex machina moment, a young version of Helena appears in a column of purple flames -- not unlike the way she was burned at the stake -- but looks exactly how Abel met her for the first time. Abel is suddenly transported back in the gardens when he saw Helena dancing among the flowers. After initially collapsing due to the loss of blood, Abel hauls himself up again and walks toward Helena, leaving behind his body that quickly disappears -- akin to how spirits/souls depart the physical body. His eyes have returned to their normal blue again. Helena teases him for keeping her waiting but is happy he kept his promise about finding her again -- regardless of his killing hundreds of people to do so. Eden's calling was never necessarily for Abel: he essentially forced it when he kidnapped Fena.
Abel does have the self-awareness to admit to Helena that he feels he can't hold her anymore because his hands are too stained with blood. But Helena doesn't care about that, or that Abel was steps away from killing her daughter -- she was just glad to see him again. As they kiss, Abel disappears, presumably ascending into the heavens.
Episode 9 of Fena: Pirate Princess revealed that Abel's love for Helena is tied in tragedy when he loses her time and time again. It shines a new light to his actions and, to a certain degree, why he's done the things he has: he was desperate and wanted to be with Helena. But does this excuse his actions? Does he do anything to redeem himself before he dies?
No. It's not until he's face-to-face with Helena that he feels an iota of regret and admits to his guilt. Nowhere in the show has he shown regret through his actions, nor has he proven that the audience should feel invested in his journey. Some of this chalks up to Fena feeling disjointed but out of the main cast, Abel is the one who got the short end of the stick in being fully fleshed out.
Up until his last moments, Abel still wanted to kill Fena and Yukimaru. His 'happy ending,' though it's still ambiguous whether or not he'll be with Helena in the afterlife, feels unearned. Happy endings don't have to be restricted to the heroes, but they still have to fit the character's arc in order for it to feel satisfactory.
Furthermore, this unearned 'happy ending' is exacerbated by poor development of Abel's characterizations. The glimpses given of Abel paint him as a villain in the shallowest terms. He's given a bit of depth with his backstory, but he goes back to being a flat antagonist soon after. What could have been a poignant send-off of Abel feels ultimately cheap in Fena: Pirate Princess' penultimate episode.