(Mod no longer under development, I've moved on to other things and no longer monitor comments)

Mod has now been tested and fully functional. No changes were needed so if you still have the alpha version file it is the exact same thing and you don't need the new one. All I did was change the readme and the name of the file to reflect it is a full release and not an alpha.
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Ever bother you how Aerin would follow Mjoll around breathing down her neck? You got married and he followed you to your new house, then stood there watching her sleep? I made this mod to fix that. I'm just now at the part of the game where I was going to marry someone and wanted to marry Mjoll, but that Aerin guy just bugged me. So, I created this mod to fix that. I haven't married her yet so it isn't 100% tested, but so far Aerin's AI routines when they're around and about in Riften are much better and less creepy stalkerish.

Another quick note, Mjoll looks different in screenshots because of my other mod.
Mjoll changed to look like Hroki http://skyrim.nexusmods.com/downloads/file.php?id=11850
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What I did.
I removed Aerin's "Follow Mjoll" AI routines. There were two of them, one general and the other that was specifically for "around the house." I then gave him mjoll's "browse market" routine so the still sort of stays around her when she's in Riften not following you and keeps him busy. I did thoroughly test this part and he doesn't stand behind her breathing down her neck anymore. More like 2 people going to the market together, sometimes looking at the same or different stalls. I wanted to keep the general feel of the game story, but without the creepy vibe the default AI gives you.

+UPDATE+ I got married to Mjoll while she was not my follower and moved her to Whiterun. Aerin did NOT follow her to the new house and stayed in Riften going about his usual routine.I also married her and moved her to Whiterun without the mod enabled and sure enough Aerin followed her there. I saved the game, enabled the mod, and after waiting an hour he started walking back to Riften. I went to the house and waited a few hours and sure enough he showed up and started following his normal routine.

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To install
Copy stop-being-a-creepy-stalker-aerin-(version)-pingy.esp into Skyrim/Data directory.
Enable the .esp in the Skyrim launcher.

To uninstall
Delete stop-being-a-creepy-stalker-aerin-0-1-a-pingy.esp
or
just disable the .esp in the Skyrim launcher.
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Effects
- Aerin no longer stands behind Mjoll breathing down her neck. If they are at a booth in the market together, he stands beside her looking at the booth instead, or he is at a different booth looking around.
- They still sit down for meals at the Black Briar together.
- Aerin chills at the house while Mjoll does her nightly patrols.
- Aerin no longer watches her sleep.
- If you marry Mjoll and move her somewhere Aerin no longer follows her to the new house.
- If already married with Aerin at your new house he walks back to Riften after a bit.
- No matter when you installed the mod, if Aerin is still alive he has a life and routine in Riften he follows independent of whatever Mjoll does.
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Conflits
Any mods which modify Aerin in any way will probably conflict.
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Credits

- MrPingy (myself) for "Mjoll changed to look like Hroki" "http://skyrim.nexusmods.com/downloads/file.php?id=11850" which was in use while taking screenshots.
- Bethesda for the vanilla game content used.
- foretrenty for "Skyrim NPC Editor" "http://skyrim.nexusmods.com/downloads/file.php?id=4554" which was used to create this mod.
- dimon99 for "DIMONIZED UNP female body" "http://skyrim.nexusmods.com/downloads/file.php?id=6709" (adult file) whose body texture is featured in Screenshots.
- mrLenski for "Coverwomen" "http://skyrim.nexusmods.com/downloads/file.php?id=3563" whose "Seamless UNP and Coverwomen Look_3" textures are featured in Screenshots.
- Xenius for "XCE - Xenius Character Enhancement" "http://skyrim.nexusmods.com/downloads/file.php?id=2356" whose eye and scar textures are featured in Screenshots (I think).
- Other mod makers whose content is included in screenshots that I may have overlooked. (I have too many frigging mods installed)

Please note that only Bethesda created vanilla content is included in the files for my mod. The files were created and edited with the Skyrim NPC Editor listed above.

Sort of Credit but not really.

Someone let me know in the comments that HolyJoe09 made a mod that does pretty much the same thing already. If I would have known that I would have saved the time/effort of making this :facepalm: I contacted him and found out we used different methods to fix it but they do both work, just differently. Here's the link to his http://skyrim.nexusmods.com/downloads/file.php?id=8480