Recommendation: Inconsistent romantic comedy that is at its weakest when dealing with the romance elements, but can be quite funny when it's going pure comedy. Not terrible, but skippable. Review covers all 3 seasons plus OVAs. Positives: + Full of the kind of insanity that you can only get from anime. Where else can you see a tank armed with a laser that turns things into catgirls? Or a magical bath that turns adult women into lolis? The series is full of the most ridiculous things you can imagine and a lot of the comedy is built around this unrestrained wackiness. + Most of the characters are fun.Laine was my personal favorite, but most get their time to shine at one point or another. I was also fond of the trio of little mascot characters (Shirou, Marduke and I forget the other one's name) and their side adventures as hard-boiled war veterans.

+ Makes the most of its ecchi tag. There are so many uncensored tiddies in this show that you stop even noticing that characters are topless at points. If you're in it for the cute alien girls, you won't be disappointed.

Negatives:

- Main romance is poorly developed and can feel uncomfortable. Valkyrie is not just physically transformed into a little girl, but has regressed in mental age as well. She can become adult Valkyrie, but only by kissing Kazuto, which leads to the very offputting sight of a 5 year old girl, in both body and mind, kissing an adult man on the lips. Leaving aside the pedophile vibes, Valkyrie just spends so much time as a child, and with Kazuto treating her more like a daughter than a girlfriend, that there is no romantic spark or chemistry between them even when she's an adult. You never really get a good sense of why they love each other.

- The main couple is just generally boring and lacking in personality. It's hard to root for such bland characters to get together. Kazuto is a generic nice guy, and Valkyrie has no personality beyond "likes Kazuto". She's often described in dialogue as cool and fiercely independent, but you never really get a sense of any of that from the show itself.

- Stumbles badly whenever it tries to get serious or tragic. Season 2 in particular is marred by this with the December Nocturne arc, which is so tonally imbalanced that it's hard to take any of it seriously.

- The art has not aged very well and it extensively re-uses previously animated scenes to cut corners. This is especially noticeable with the magical girl transformations, which are often repeated in full multiple times per episode.

- Too much stalling with the romance. It has a sitcom-like tendency to always reset to the status quo, with Kazuto and Valkyrie's marriage being called off multiple times in increasingly improbable ways, and still remaining unresolved after 3 seasons. For a couple that already lacks heat, this makes it even harder to care about them