help me remember an anime

[Amethyst]

ok i got a question then

I saw this anime a long time ago where there was a guy who was elderly and he was part machine also all i remember is that they were trying to stop him and eventually when they did he exploded or something and the world blew up and the anime ended. But the anime seemed to have a strong sense of care for elderly people like he was at a nursing home

Also i saw an anime that was in outer space and there was this huge metal computer like thing that seemed to almost have a God quality but further then that i can't remember except that i think it had a rust color.

Knights of Ramune? It is rather echi, so on first glance might be considered Hentai (lot of nudity)

But then again... maybe not... laugh... gomen