(This review contains unmarked spoilers - if there could ever be spoilers for such a thing)

Ai (Love) is a 2012 ONA that is perhaps most famous because of its length. Let's first talk about the elephant in the room: Ai is 7 seconds long. Which means that...
...this anime is so short you could watch it several times in the time it takes you to read this review,
...this anime is so short you could watch it approximately 210840 times in the time it takes you to watch all of One Piece at the time of writing,
...this anime is so short that even taking the decision of watching it takes longer than actually watching it,
...this anime is so short that even element nihonium outlives it (how ironic)

I could go on, but you get the point.

Now, let's examine what happens in these 7 important seconds. We are presented with a shot of a person, dressed in blue, seemingly struggling against something. As time passes, the shot gets more blurry and distorted, while it gradually fades to black.

What a brilliant reflection on love! The person struggling clearly reflects the constant struggle that love is - even if it is requited, as commiting to a healthy relationship requires a great degree of personal effort and maturity. The progressive distortion of the image symbolizes how problems eventually pile up as things settle down in a relationship, after an initial honeymoon phase in which everything seemed fine and perfect. The fade to black is a constant reminder that time is slowly fading our lives away, and thus we have limited time to fix our issues before death comes to knock our doors.

All of these metaphors are, of course, nothing but a useless distraction from Ai's true purpose. See, Ai has a collection of unique traits that makes it the perfect filler for your anime list, making you seem more anime-experienced than you actually are. Of course, its length is a great advantage - after 7 seconds, you're done, and you can already add it to your anime list. This way, you don't waste your time watching something like Mars of Destruction. But, furthermore, Ai has no sound or dialogue, so you can literally watch it anywhere your internet connection allows without bothering the people around you. Since Ai consists of a single camera shot, you could even add it to your list after just looking at the image in its Anilist page - after all, that's all there is to it (for 7 seconds). And unlike, say, Takena Nagao's short ONAs, Ai is devoid of any shocking or offensive content, or of any impact whatsoever in its audience.

Veredict: 5/10. Ai has a unique, very specialized role as a perfect filler for your anime list. Too bad it can't possibly serve any other purpose.