The Rick and Morty

It's been approaching to summer end. --- The end of summer is approaching.

I watched "Rick and Morty" at first time. --- I watched Rick and Morty for the first time.

My friend taught me the TV animation. --- My friend told (教えてくれた) me about this animation. ('animation'より'show'のほうが自然なのかもしれません) 

So I thought it was very interesting story after watched. --- After watching it, I thought it was very interesting.

First of all, I thought Japanese people can't never make like that. --- First of all, I thought Japanese people couldn't ever make something like that.

I might just don't know like that in Japan. --- There might be something like it in Japan, but I don't know about it.

I admired the story. --- I liked the story.

Second of all, There are many attractive monsters in that. --- Secondly, it had lots of interesting monsters. ('attractive'ってはだいたい性的に格好について使われています)

It was cool and have taste in monster. --- This show was cool and had well-designed monsters!