His father introduce to her new future mother, he cannot believe himself that her future mother is is the same age as her and living together with him because his father going overseas or whatsoever.. but the most shocking is she attending the same school as him...

is there a manga could be exist?

Yep, it's Mama wa Doukyuusei.

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"Officially, this machine doesn't exist, you didn't get it from me,
and I don't know you. Make sure it doesn't leave the building."

Must not..... make snide.... remarks..... about..... horrible english...... Also..... no yoda..... jokes.

Seriously though dude, not speaking great english on a message board on the bloody internet is fine and all, but your request doesn't even make sense half the time.

Is the main character your talking about a guy or a girl? since you switch it around constantly it's very unclear.
From what I can deduce however, it almost seems like your talking about Mama wa Doukyuusei

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Do but despise reason and science,
The highest of all human gifts -
Then you have surrendered to the Devil
And must surely perish. - J.W. von Goethe

WOW Thanks....

Sorry my english is bad....