Not advisable to watch if you don't want to waste time, can't tolerate annoying voice and looking for a good story.

If you like Gate: Jieitai Kanochi nite, Kaku Tatakaeri, I suggest you also try watching this.
This kind of anime is good after watching the whole series, but I didn't expect that I would love this because the main girl is Louise and I find her annoying in season 1.

Story: 5/10
Louise and her familiar Saito will go to Romilia to meet the Pope because all the void mage should work together to prevent the Ancient Dragon from destroying everything.
It's sucks how things end for Joseph, his presence makes the series interesting.
It's very cliche but at the end the power of love and friendship saves the day. It got some filler episodes and some fan service.

Characters: 10/10
The characters are likable, some characters have a great development like Agnes and Colbert-Sensei
Louise: She was annoying at first, but she becomes a bit likable after casting spell like EXPLOSION!!!.
Saito: Your typical perverted MC but unlike harem MC he chooses a girl.
Guiche: His character is just funny the Mr. handsome guy.
Tiffania: Saito's second master, she got a lot screen time in this season.
Siesta: The lewd maid, without her I can't tolerate watching it because of Louise.
Henrietta: Making Louise and her rival Siesta works together (a bigger threat for Saito)
Charlotte: Another princess in Saito's harem :v
Derflinger: best bro and a sword.

Art: 8/10
The art is good, I didn't see any mutant face and they didn't use CGI on the small dragons. The CGI Ancient dragon looks good also.

Sound: 8/10
The opening and ending song are good , although I might not remember any of it after watching it because the only sound that I will remember in this anime was Louise's voice.

Enjoyment: 9/10
I'm just biased because I watch this late and it reminds me of a lot of anime like Goblin Slayer because of the Double Moon, GATE for the Jet and modern equipment and Konosuba for EXPLOSION!!!!
Once you get used to Louise, everything becomes fine. It's very tiring to watch Saito and Louise fighting every time, but their relationship was so strong that no event or hot girl can destroy it. I actually enjoy the filler episodes more than the actual story.

I love to watch the progress of every girl in the show with Saito.