Looking for a shoujo/josei in which the heroine starts off in a relationship but ends up with an unsuspecting second guy.
For example, Cat Street. I did not expect for the girl to end up with

that black-haired guy.

Also, Tonari no Atashi. I was about to drop this manga until I read a spoiler that said

the girl was going to end up the guy who doesn't even make his first appearance until a couple chapters into the series.

Help is much appreciated! Thank youuuu!

Not, sure but you can give Bitou Lollipop a try, if ...

... It's okay, when the female main character doesn't end up with the readers first guess, but a second guy showing up within the next chapter and he isn't as indicisive as the first guy - and younger than her by a few (about 2?) years.

"It's like love is a bonus in your life. Even without it, I'm just fine. I don't feel like pointlessly searching for it. You don't have to make yourself unhappy." (Ookami Shoujo to Kuro Ouji)

"Why does it rain?" - "To create drama." (Drops (Andou Yuki))

Moe Kare is one that I could think of
Fruits Basket also

I've been reading alot of shoujo mangas but it's rare coming across that type you are looking for.

Technically, Hana Yori Dango is like that, because he ended up with the guy who comes after. And yeah, it's kind of hard to find a plot like that.

I've read all of those already, but thanks anyway! 🙂

I know that plotline is pretty rare, which is why I decided to ask the internet haha.

Maybe the oneshot End of Summer from Love Stalking!?

Maybe this can help:

[url]http://www.mangaupdates.com/showtopic.php?tid=31503&page=1#post555994[/url]

It's a topic I did a while back and as well as my topic somebody linked me to three other similar ones.
I think you could find some good ones in there.

Basically I started the topic cuz I was annoyed at how many mangas I'd read where the main character ends up with the first guy who shows up in the first chapter.

As a personal recommendation, how about brilliant magic

Hitohira no Koi ga Furu fits 🙂

Edit:
Now, that I think about it, you can also give Kitchen Princess a try. The boy she ended up with is kind of her second (but I can't say too much without spoiling everything 😉 )
Also maybe Shugo Chara!? Amu from the start is pursuing/in love with one boy, but ends up with another (but reader can see that she is clearly attracted to him).

[img]https://dreamuniverse.files.wordpress.com/2014/10/gilgamesh1.jpg[/img]

http://www.mangaupdates.com/series.html?id=1143 might fit

OMGWTFBBQ!

Parfait tic !! Think you will like this one, do not know if it is fullly translated though, so in that case you have to wait and see a little longer to see who she ends up with

So Bad

http://littleworldofthebigfool.blogspot.com/
[img]http://myanimelist.net/signature/melis_1995.png[/img]

Makimodoshi no Koi no Uta ?? since this one not having love triangle like the others. And this one is my Favorite. because how the story goes... 🙂

A person’s mental age did not grow with age, but grew with experience - by After I Livestreamed Raising Cubs I became the Wealthiest in Interstellar

I don't know if you have read it but Hirunaka no Ryuusei is EXACTLY what you need ^^
https://www.mangaupdates.com/series.html?id=66014

I've read some where it comes out of nowhere where the girl/guy ends up with the 2nd person, but most of that time that second person was the one who they were intended to be with all along in the grand scheme of things. Though the times where the character was better with the first girl/guy and them going to the next was out of nowhere and/or made no sense. I call it an "ass pull". It's like the author decides to be "edgy" and changes it for no reason or goes another way out of the "norm". Problem is those kinds of "ass pulls" usually don't fit in the rest of the story and kinda ruins it.