 If you liked
Mahou Shoujo Madoka★Magica
|
 ...then you might like
Strawberry Fields wo Mou Ichido
|
Strawberry Fields Once Again and Puella Magi Madoka Magica are two 3-volume series focusing primarily on two girls; there are girls' love/GL/lesbian elements, which could be a bit of a spoiler for the latter, but the series is kinda notorious for it along with other things, and no point hiding that for the latter. There is also another common plot similarity, but that one is definitely a spoiler for the latter; I suppose just keep note of past, memories, and seemingly unlikely relationships (whether romance or platonic) as common themes.