<p>Out of universe, I couldn't find anything except the <a href="https://wiki.gfkari.com/wiki/Miss_Monochrome" rel="nofollow noreferrer">Girlfriend Beta wiki page</a> that senshin mentioned, which puts down her age and birthday as "???". </p>

<p>In the universe of the anime series, Miss Monochrome's birthday/activation date is probably unknown as well. As we see in Episode 9 of Series I, Miss Monochrome was created by an advanced human civilization that existed before the beginning of known prehistory. This civilization was wiped out by aliens in a human hunt.</p>

<p>After the death of her rival, a past-life version of Kikuko, Miss Monochrome sits at one spot and waits until her memories fade and her battery goes out and she disappears. Life evolves again on Earth, and millions of years later, she is reactivated by a pair of medieval Japanese villagers who luckily have an AA battery to put in her power stand. </p>

<p><a href="https://i.sstatic.net/FzWbLm.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/FzWbLm.png" alt="a long time passed"></a>
<a href="https://i.sstatic.net/3reXfm.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/3reXfm.png" alt="she continued to wait"></a>
<a href="https://i.sstatic.net/ZX9jYm.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/ZX9jYm.png" alt="life was born on the earth once more"></a>
<a href="https://i.sstatic.net/atELqm.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/atELqm.png" alt="some sort of primitive tetrapod"></a></p>

<p>The important part here is "her memory faded". Miss Monochrome would not remember her own birthday / activation date anymore, and anyone else who might have known died over 100 million years ago. Even if she did remember, it would be in the calendar system of the ancient civilization. If Miss Monochrome didn't know how to translate this into the Gregorian Calendar, no one would be able to, and I somehow don't think that learning the inner workings of the calendar was high on her list of priorities, even before she became brain-damaged. </p>

CC BY-SA 3.0
2017-03-23T19:05:55.180Z
One possibility that didn't occur to me at the time I wrote this answer is that she might remember her "birthday" in some sort of epoch time in a unit defined in terms of a natural feature, like number of cycles of the radiation produced by a cesium 133 atom since her activation, and then it would be possible to translate it into a Gregorian date. But since her memory faded, this probably isn't the case.
Torisuda
CC BY-SA 3.0
2016-02-28T19:24:32.317Z
2016-02-28T19:24:32.317Z
Torisuda
<p>Title says it all. When is Miss Monochrome's birthday? Wikipedia only said that she first appeared in Horie Yui's concert in 2012 but mentioned nothing of her birthday.</p>

CC BY-SA 3.0
2016-02-22T05:50:34.620Z
FWIW, a quick bit of googling indicates that Miss Monochrome apparently appears in Girlfriend (Beta), and while some of the other girls in the game have their birthdays listed, Miss Monochrome's birthday is explictly not given.
senshin
CC BY-SA 3.0
2016-02-27T11:56:09.093Z
well, in my opinion, if you take into account that miss monochrome is a character created and voiced by voice actress Yui Horie, one may argue that the character is a representation of herself, if that were the case (and taking into account that an specific birthday is unknown) their birthdays would be the same, September 20.
thePiGrepper
CC BY-SA 3.0
2016-03-02T04:18:35.563Z
^ Googling "[Miss Monochrome's birthday](https://www.google.com.sg/search?q=%E3%83%9F%E3%82%B9%E3%83%BB%E3%83%A2%E3%83%8E%E3%82%AF%E3%83%AD%E3%83%BC%E3%83%A0+%E8%AA%95%E7%94%9F%E6%97%A5)" in Japanese returns Yui Horie's birthday
Aki Tanaka
<miss-monochrome>
When is Miss Monochrome's birthday?
# When is Miss Monochrome's birthday?
Posted by: username_0 on 2016-02-22
Title says it all. When is Miss Monochrome's birthday? Wikipedia only said that she first appeared in Horie Yui's concert in 2012 but mentioned nothing of her birthday.
**Tags:** miss-monochrome
> **Comments:**
> **username_1**: FWIW, a quick bit of googling indicates that Miss Monochrome apparently appears in Girlfriend (Beta), and while some of the other girls in the game have their birthdays listed, Miss Monochrome's birthday is explictly not given.  
> **username_2**: well, in my opinion, if you take into account that miss monochrome is a character created and voiced by voice actress Yui Horie, one may argue that the character is a representation of herself, if that were the case (and taking into account that an specific birthday is unknown) their birthdays would be the same, September 20.  
> **username_3**: ^ Googling "[Miss Monochrome's birthday](https://www.google.com.sg/search?q=%E3%83%9F%E3%82%B9%E3%83%BB%E3%83%A2%E3%83%8E%E3%82%AF%E3%83%AD%E3%83%BC%E3%83%A0+%E8%AA%95%E7%94%9F%E6%97%A5)" in Japanese returns Yui Horie's birthday  
---
## 1 answers
### Answer by username_4 on 2016-02-28. Score: 4 | Accepted answer
Out of universe, I couldn't find anything except the [Girlfriend Beta wiki page](https://wiki.gfkari.com/wiki/Miss_Monochrome) that senshin mentioned, which puts down her age and birthday as "???".

In the universe of the anime series, Miss Monochrome's birthday/activation date is probably unknown as well. As we see in Episode 9 of Series I, Miss Monochrome was created by an advanced human civilization that existed before the beginning of known prehistory. This civilization was wiped out by aliens in a human hunt.

After the death of her rival, a past-life version of Kikuko, Miss Monochrome sits at one spot and waits until her memories fade and her battery goes out and she disappears. Life evolves again on Earth, and millions of years later, she is reactivated by a pair of medieval Japanese villagers who luckily have an AA battery to put in her power stand.

[![a long time passed](https://i.sstatic.net/FzWbLm.png)](https://i.sstatic.net/FzWbLm.png)
[![she continued to wait](https://i.sstatic.net/3reXfm.png)](https://i.sstatic.net/3reXfm.png)
[![life was born on the earth once more](https://i.sstatic.net/ZX9jYm.png)](https://i.sstatic.net/ZX9jYm.png)
[![some sort of primitive tetrapod](https://i.sstatic.net/atELqm.png)](https://i.sstatic.net/atELqm.png)

The important part here is "her memory faded". Miss Monochrome would not remember her own birthday / activation date anymore, and anyone else who might have known died over 100 million years ago. Even if she did remember, it would be in the calendar system of the ancient civilization. If Miss Monochrome didn't know how to translate this into the Gregorian Calendar, no one would be able to, and I somehow don't think that learning the inner workings of the calendar was high on her list of priorities, even before she became brain-damaged.
> **Comments:**
> **username_4** (2017-03-23): One possibility that didn't occur to me at the time I wrote this answer is that she might remember her "birthday" in some sort of epoch time in a unit defined in terms of a natural feature, like number of cycles of the radiation produced by a cesium 133 atom since her activation, and then it would be possible to translate it into a Gregorian date. But since her memory faded, this probably isn't the case.  
---
