Galio's and Poppy's Friendship all makes sense now!

Galio is for the most part inanimate, but cognitive, and only regains mobility during times of war and onslaught. Poppy is a near immortal embodiment of Demacian mettle and determination in the form of an adorable Yordle girl. Poppy is pretty much the only creature in Demacia, except maybe Shyvana (and even then, she's still mortal), who would be alive to see and get to know Galio when he is animate, and she would really be the only friendly face he will always recognize as the years, decades, and centuries roll by. She would also be the only person in the city who would truly know that Galio is actually alive, as most humans in their shorter lifespans probably wouldn't ever see Galio alive unless they lived during the time of a great war and siege of Demacia. Poppy is his only friend because anyone else he would befriend would likely die of old age before he woke up again. Poppy would also be the one to sit by him and keep him company, because she knows he'll get lonely and she is the only one in every generation that is aware that he is listening. This is why Poppy is friends with Galio, and it's beautiful, sad, and bittersweet.