Natie

Natie is the het ship between Nathan Adams and Katie Forester from the Yokai Watch fandom

Yokai Watch 1 (Anime)
The first season of the anime begins with Nathan, his friends and Katie trying to catch insects, Nathan was looking for the most interesting insects to surprise Katie, when he finally found a really interesting insect, he chased it until he reached a strange machine that asked for food, Nathan when giving a coin enters the world of the Yokais and meets his Yokai butler, Whisper.

In the first season Nathan and Katie interacted on occasion, Nathan had claimed that he liked Katie, but Katie only saw him as a friend.

Yokai Watch 2 (Anime)
In the second season Nathan does not interact much with Katie, only a few times in which Katie was being possessed by some yokai and Nathan was saving her.

WakuWaku Nyanderful Days
The manga shows an alternate reality to the original, where Katie gets the yokai watch instead of Nathan.

When in the manga Katie realizes that Nathan is being possessed by a yokai, she does not hesitate to help him, then Nathan realizes that everyone was making fun of him and feels sorry for him, but Katie calms him down.

After a beauty-obsessed yokai comes to school, Katie gives the Yokai an aid to make him look better, Nathan thinks Katie is cute and tells him, she just blushes and thanks him, showing that Nathan has a loving interest in her. In a short moment in the manga, Nathan admits that he thinks Katie is the prettiest girl in school.

In Chapter 9, Nathan is seen helping Katie get ready, when she finishes getting ready Nathan compliments her.

Yokai Watch: Shadowside
This season is 30 years after the first seasons of the anime, in Shadowside Nathan and Katie are 41 years old, they are married and have two children, they look happy as a family

Summer Adams
Summer is the eldest daughter of Nathan and Katie, she appears for the first time in Shadowside, she is 12-13 years old, her hair and eye color is brown and she also has a yokai watch

Tate Adams
Tate is the youngest son of Nathan and Katie, he also appears for the first time in Shadowside and is very similar to his father when he was young, he is 11 years old, his hair color is brown and his eyes are also brown

Fanon
Natie is a very popular ship within the fandom, since Nathan and Katie are often seen together in the anime and manga, also because at the end of the anime they remain together as an official couple