user2567: What does the "teehee" expression mean? and What is the origin of this facial expression with one's tongue sticking out? both involve expressions in which a character's tongue is sticking out, but I don't think the "teehee" question should be regarded as a duplicate of the other one. Should the "teehee" question stay closed as a duplicate of the other one?
The "facial expression" question comes with specific examples, at least one (if not all) of which are parodies of peko-chan, as Krazer points out. However, I don't think a reference to peko-chan is necessarily something where a character is trying to cover up a mistake they made, which I believe is the expression being asked about in the "teehee" question.
"tehepero" is a word that refers to specifically this latter usage (Japanese source for definition, Japanese youtube video of it being used outside of anime). The "teehee" question may even be too much of a "culture" question (see Where should we draw the line with "culture" questions?) for this site, but if the question stays, I don't think it's a duplicate.
Full disclosure: This issue is complicated by the fact that the tongue of tehepero may have it roots in peko-chan (Japanese source), and even if it doesn't, it's certainly been associated with her (Japanese source 1 Japanese source 2). 

user24: The points you make are good. I was on the fence with this one. I didn't vote to close as a duplicate when I first saw the question, but just linked to the other question. When I later saw it in the review queue, I deliberated quite a bit before deciding to close as a duplicate. I think when I did decide this, I was probably focusing too much on the particular instance from the image, and not enough on the actual question (which is at least nominally quite different from my earlier question).
Anyway, the two tropes are not obviously the same, so the question probably deserves to be reopened for now. The better course of action would be to add an answer linking to the other question and mentioning that the two are related. If others think it is too broad or not anime-based for the question to stay open it could be closed for other reasons, but calling this a duplicate is probably a bit of a stretch.
I've voted to reopen the question.
Update: the question has been reopened

2567: <p><a href="https://anime.stackexchange.com/questions/6224">What does the &quot;teehee&quot; expression mean?</a> and <a href="https://anime.stackexchange.com/questions/2995/">What is the origin of this facial expression with one&#39;s tongue sticking out?</a> both involve expressions in which a character's tongue is sticking out, but I don't think the "teehee" question should be regarded as a duplicate of the other one. <strong>Should the "teehee" question stay closed as a duplicate of the other one?</strong></p>

<p>The "facial expression" question comes with specific examples, at least one (if not all) of which are parodies of <a href="http://en.wikipedia.org/wiki/Fujiya_Co." rel="nofollow noreferrer">peko-chan</a>, as Krazer points out. However, I don't think a reference to peko-chan is <em>necessarily</em> something where a character is trying to cover up a mistake they made, which I believe is the expression being asked about in the "teehee" question.</p>

<p>"tehepero" is a word that refers to specifically this latter usage (<a href="http://blog.livedoor.jp/seiyumemo/archives/7022095.html" rel="nofollow noreferrer">Japanese source for definition</a>, <a href="http://www.youtube.com/watch?v=jJfU4-tVBl4" rel="nofollow noreferrer">Japanese youtube video of it being used outside of anime</a>). The "teehee" question may even be too much of a "culture" question (see <a href="https://anime.meta.stackexchange.com/questions/610/">Where should we draw the line with &quot;culture&quot; questions?</a>) for this site, but if the question stays, I don't think it's a duplicate.</p>

<p>Full disclosure: This issue is complicated by the fact that the tongue of tehepero may have it roots in peko-chan (<a href="http://dic.pixiv.net/a/%E3%81%A6%E3%81%B8%E3%81%BA%E3%82%8D(%E3%83%BB%CF%89%3C)" rel="nofollow noreferrer">Japanese source</a>), and even if it doesn't, it's certainly been associated with her (<a href="http://www.oricon.co.jp/news/video/2028230/full/" rel="nofollow noreferrer">Japanese source 1</a> <a href="http://blog.livedoor.jp/amecome/archives/52045381.html" rel="nofollow noreferrer">Japanese source 2</a>). </p>
 24: <p>The points you make are good. I was on the fence with this one. I didn't vote to close as a duplicate when I first saw the question, but just linked to the other question. When I later saw it in the review queue, I deliberated quite a bit before deciding to close as a duplicate. I think when I did decide this, I was probably focusing too much on the particular instance from the image, and not enough on the actual question (which is at least nominally quite different from my earlier question).</p>

<p>Anyway, the two tropes are not obviously the same, so the question probably deserves to be reopened for now. The better course of action would be to add an answer linking to the other question and mentioning that the two are related. If others think it is too broad or not anime-based for the question to stay open it could be closed for other reasons, but calling this a duplicate is probably a bit of a stretch.</p>

<p>I've voted to reopen the question.</p>

<p>Update: the question has been reopened</p>
