Kyranol

Oh and psyren, how the hell did i forget this?! (amazing manga)

Dice the cube that changes everything

green boy

automata

moon ah

ultimate legend: Kang hae hyo

Special martial arts extreme hell private high school (if you're alright with reading a rlly weird story with rlly weird character, but its such a funny webtoon)

dr.frost

over steam

cant see can hear but love

Pinocchio

nineteen, twenty-one

Dear, only you dont know

between you and i

The god of highschool

And thats about it, have fun reading

Ruler of the land

Eureka seven

dengeki daisy

yamada kun to 7 nin no majo

akame ga kiru

kampfer

uwagaki

kaichou wa maid sama

molester man

liar x liar

7 seeds

warau kanoko sama

koi dano ai dano (sequel to one above)

aku no hana

wallman (beware spoilers to sun ken rock)

spirit circle

noragami

kubera

hibi chouchou

soredome sekai wa utsukushii

Dice the cube that changes everything

again

shinrei tantei yakumo

taboo tattoo

sousei no onmyouji

rainbow

Dragons rioting

blood lad

bonnouji

tasogare otome x amnesia

id

1/2 prince

countrouble

ore ga akuma de aitsu ga yome de

Hana to Akuma (its shoujo but so worth the read)

seishun forget

Magico (iwamaoto naoki) - Highly reccomended

super dreadnought girl 4946

immortal regis

cavalier of the abyss

tokyo crazy paradise (shoujo but still highly recommended)

Rave master - highly recommended

rurouni kenshin - highly recommended

Have fun reading

Try out kore wa koi no hanashi. Its a rlly cute manga about a middle aged? (i forgot but i know he was quite old i believe late twenties or early thirties?) writer who doesnt rlly have any passion or inspiration for a story when a young girl suddenly appears in his backyard and asks if she can take care of a cat and let it stay in his yard. You can read it to find out the rest
Try it out its rlly good plus its a shoujo manga

Another one is keishichou tokuhanka 007. This one is kind of a long shot but it is a shoujo with good story, romance characters and it centers around a girl who has the power to remember memories from objects and people and a detective who is like 7 years older than her.

This one is the opposite of what you want but its still good none the less. Its Oyome ni ikenai, this one centers around a middle aged woman who is not able to take care of herself so she hires a house worker (male maid?) who is in highschool to do the house chores and cook food for her. Its quite a cute story.

Ore ga akuma de, aitsu ga yome de... This is such a sweet and cute manga i nearly fainted. It may be a shounen but its still sooooooooooooooo good. Its about a demon who is sent to earth trying to find a contractor so he can fulfill their wish while they exchange it for some of their life. He meets up with a young girl (in elementary if my memory serves correct) and she makes a wish that she wants the demon to be her husband thinking he was an angel! Hilarity and cuteness ensues, it also has quite a good story line. The ending was a bit rushed but overall a rlly good manga i highly reccomend it. 

Hana to Akuma, if you have not yet read this manga hurry up and read it right now! It is such a sweet story that is interesting, funny, sweet, happy and at the same time sad. its about a demon who finds an abandoned child and decides to raise her and yeah... Not gonna say anything else as it may spoil some of the story but it rlly is an amazing manga personally one of my favourite shoujos.

And yeah... Thats about it. Anyways all of these are rlly good so check them out