Mahoromatic: Motto Utsukushii Mono

both animes have a android character with limted time left to live, they both have great story lines in my opinion  

A girl who was sent to a main male lead, then falls in love with him, but carries a dark past. Also, another girl who suddenly enters a group of friends and some similar events occur cos of the new member. Both feature much slice-of-life and school life. 

Both are series about two powerful maids, in Mahoromatic an android and a cyborg, and in Steel Angel Kurumi two androids, living as sisters in the service of a young boy. The maid androids in either series have some similar personality quirks, and struggle against enemy forces. 

They both have a similar story, where the leading girl is sweet, but very powerful, and also from outer space. Also, they both are by Studio Gainax, and have the same character designers.