I'd recommend 'Nightshade'. In this manga, the English half-vampire girl character has a complex personality and goes through many adventures. The art style is also quite captivating.
Well, 'Twilight Twins' could be one. It has the element of half vampire twins and is set in an English-like setting.
There are several possibilities. One such manga could be 'Blood Moon Chronicles' where a red-haired half vampire girl from England plays a central role.
I'd recommend 'Kemono Jihen'. It has a diverse cast of half animal kids and explores their adventures and challenges. The plot is full of twists and turns that keep you hooked.
English slime girl mangas usually have fantasy elements and adventure plots. The slime girls might have special powers or abilities that drive the story forward. Also, the settings can vary from magical kingdoms to modern cities.
You might want to check out 'Blood Lad'. It presents an interesting take on half vampires and is available in English. The story combines action and drama with the theme of half-vampire characters.
I'd recommend 'Patlabor'. It has a female police officer character and it's known for its detailed mecha designs and interesting storylines. Another one could be 'Dirty Pair', where the female duo takes on various law enforcement missions.
One popular manga is 'Dragon Maid', where the main character Tohru is a dragon girl. It's loved for its cute art and fun story.
There's 'The Lost Memories'. This manga follows a girl with amnesia as she embarks on a journey to recover her past and uncover the truth. It has a lot of mystery and drama.
I'd recommend 'The Legend of the Celt Maiden'. It offers a rich and immersive world with a strong Celt girl as the protagonist. The story combines elements of fantasy and history, making it really engaging.
One could be 'Dragon and Spider Girls' which has unique character designs and an engaging plot. It's gained quite a following.