I guess he is getting killed in the first ep of GoT

Yeah his casting does seem to indicate that this will be his last season of Thrones. Don't think he'll get killed in the first episode though, the middle of the season or near the end is my guess. Start the speculation now on how he will die: my guess because the Faith Militant don't like gay people, the High Sparrow will have him executed.

Pear of Anguish 

It's hot... but not as hot as the night Johnny Viti got married...

Doesn't his character get seriously injured (near death) when last mention even in the book? So how is this surprising?

...add The Defenders to the mix and three shows could be difficult to juggle.

His injuries in the last book are disposable as they were sustained while taking Dragonstone, which hasn't been reported as lost by Stannis or any other Lord. Might have been a lie by the Tyrell to keep Cersei in the dark while plotting something else. The story was a bit unbelievable as it Loras continue fighting with arrows in his body and after a boiling oil bath.