End of the Netflix anime the pet girl of sakurasou is not completely clear?

Will there be a second season? (Spoiler)

Spoiler:

Can one assume that shiina and sorata will come together?

Because the internet doesn't really officially confirm that there will be a second season.

Nothing more, the novel has been completely adapted

Anime like this almost always have an open ending.

Nothing more will come.

Nope.
In the anime only the first 6 (and parts of the 7th) volumes were adapted.
Volumes 7-10 are not included in the anime.

The anime only goes up to the 6th volume of the light novel (with parts of the 7th).
Volumes 7 to 10 were not adapted as anime.

That there could be a second season is theoretically possible, but very, very unlikely.
The anime is from 2012 (0212-2013) and covers genres that are currently not in trend, so it would be worthwhile to revisit.
Isekai anime are currently very popular (which is why there will finally be a third season of Log Horizon), but high school love dramas with and without ecchi are not really. Admittedly, they belong to the "standard stuff".

It is also relatively common for anime to only adapt part of a manga / novel, or to leave out the actual ending and end the anime with an open ending.
Presumably this should serve as an incentive to buy the mangas / novels.

But on the Internet you can find people who have read the last volume and reveal something about the end.
https://frogkun.com/2013/08/13/the-ending-of-sakurasou-no-pet-na-kanojo-sucked-light-novel-spoilers/

"In short": (Attention spoilers)

Sorata and Mashiro get together
Nanami leaves the Sakurasou shortly afterwards (and thus practically the story)
In the last volume you can see that she cut off her ponytail (to show that she is "over Sorata")
Jin and Misaki get married
Nothing changes between Rita and Ryuunosuke
There's more background information on the newcomers
New boy likes new girl, new girl likes Sorata → standard love triangle fuss
It is unclear whether a new girl and a new boy will get together
Mashiro and Sorata do it with each other (something that doesn't normally appear in this type of story / anime. Maybe that's why the anime stop)
Sorata's personality changes by 180 ° → he becomes a downright pervert
Mashiro and Sorata split up because the relationship is not good for either of them
Timeskip 4 years into the future, Sorata is an adult
Sorata and Mashiro get back together
Sorata's game designs are becoming increasingly popular
Mashiro's mangas become "classics"
Nanami gets some roles as a voice actress
Happy ending (or something…)

Jin and Misaki get married

That was already clear in the anime.

Getting engaged = / = getting married

And there was no wedding in the anime, no.

But didn't she hand in the wedding papers when Jin was studying or something?