user128: I have created two new tags (though one was created for me because I was too slow!). One for [clannad] and for [reborn]. 
I set the description out like this. I'll be using Kuroshitsuji/Black Butler as an example:

A shounen manga and anime, focusing on the avenging young boy who is known as the "Queen's Loyal Dog", Ciel Phantomhive and his curious, cat-loving, demon butler, Sebastian Michaelis. 

I thought it was good because it gives a description of the main characters and their names - plus a short and not too revealing snippet of the story. I thought the genre was also an important feature. The template I would use would be:

A [genre] anime [and/or] manga, focusing on the live(s) of the [short description], [main character's name] and the [short dedcription], [main characters nane]. 

For another example, Full Metal Alchemist:

A shounen manga and anime, focusing on the lives and adventures of the brothers - a short, bad-tempered but alchemistically talented Edward Elric and his brother, a gracious, polite and loving young boy with a hardship beyond fair, Alphonse Elric. 

Or Chobits, perhaps:

A seinen anime and manga focused on the farm-boy come Tokyo University Motosua and his encounter with a gorgeous and glowing personal computer robot, known as a 'persocom' named Chii. 

I didn't really know how a should do them properly, so I thought I may as well discuss the idea. I don't mean for it to be sent in concrete, but just as a trial-and-error theory. 

user28: I think the format you suggested is quite good, the genre and main character(s) is important, but I will also like to suggest including the theme or plot direction, something like:

A shounen manga and anime, focusing on the lives and adventures of two
  brothers; Edward and Alphonse Elric, who through a series of events
  studies and uses alchemy in their search for the legendary
  philosopher's stone.


128: <p>I have created two new tags (though one was created for me because I was too slow!). One for [clannad] and for [reborn]. 
I set the description out like this. I'll be using Kuroshitsuji/Black Butler as an example:</p>

<blockquote>
  <p>A shounen manga and anime, focusing on the avenging young boy who is known as the "Queen's Loyal Dog", Ciel Phantomhive and his curious, cat-loving, demon butler, Sebastian Michaelis. </p>
</blockquote>

<p>I thought it was good because it gives a description of the main characters and their names - plus a short and not too revealing snippet of the story. I thought the genre was also an important feature. The template I would use would be:</p>

<blockquote>
  <p>A [genre] anime [and/or] manga, focusing on the live(s) of the [short description], [main character's name] and the [short dedcription], [main characters nane]. </p>
</blockquote>

<p>For another example, Full Metal Alchemist:</p>

<blockquote>
  <p>A shounen manga and anime, focusing on the lives and adventures of the brothers - a short, bad-tempered but alchemistically talented Edward Elric and his brother, a gracious, polite and loving young boy with a hardship beyond fair, Alphonse Elric. </p>
</blockquote>

<p>Or Chobits, perhaps:</p>

<blockquote>
  <p>A seinen anime and manga focused on the farm-boy come Tokyo University Motosua and his encounter with a gorgeous and glowing personal computer robot, known as a 'persocom' named Chii. </p>
</blockquote>

<p>I didn't really know how a should do them properly, so I thought I may as well discuss the idea. I don't mean for it to be sent in concrete, but just as a trial-and-error theory. </p>
 28: <p>I think the format you suggested is quite good, the genre and main character(s) is important, but I will also like to suggest including the theme or plot direction, something like:</p>

<blockquote>
  <p>A shounen manga and anime, focusing on the lives and adventures of two
  brothers; Edward and Alphonse Elric, who through a series of events
  studies and uses alchemy in their search for the legendary
  philosopher's stone.</p>
</blockquote>
