Author Tract: The Take That against, or Deconstruction of, the Tsundere archetype. It is given a disproportionate amount of attention, and seems out of place if you don't know the critical intent (see the blog post below).
Also, she was faking it to infiltrate his house. David knew she was either tsundere or faking (though he mistook her reason for greed) and didn't want either in his house.
...especially when you're asking an elder god, seeing as how they have very little understanding of humans, let alone human metaphors and euphemisms. See Everybody's Dead, Dave below for just how bad this can get.
Narla hires a ride in exchange for "anything you want". The guy wants to never have to worry about bills again, which she considers an easy one. So many lovely interpretations of that...
Bedmate Reveal: On the part of the author to the audience, when David casually tells Shubbie that Nancy kisses differently than she does. This is the first hint that David and Nancy's romance has progressed that far.
Cool Big Sis: Shubby literally introduces herself as this. Considering she's Shub-Niggurath, how straight or subverted the trope is remains to be seen.
This plus Big Beautiful Woman and Hot Mom: Shubbie, the "default" form of Shub-Niggurath, "The Black Goat Of The Woods With A Thousand Young". Given what she is, she's got about the right figure for it.*
the "thousand young" part, not the "black goat" part. No malicious intent or insult towards the physique of the average goat is intended.
Dark Is Not Evil: Despite what they are, most of the Lovecraftian entities really seem to be more curious about how humans act than interested in eating them. Nancy herself is fairly nice, deciding to help Dave rather than kill him in order to study his desire to be loved. The Sleeper is literally enamored of Dave for being kind to frogs and the forest. Shubbie seems genuinely amused by / interested in Dave and his relationship with Nancy. The only exception to this (so far) is the Shoggoth, and she seems to be more of a wild animal that needs to be trained than genuinely malicious.
Did You Just Romance Cthulhu?: Why yes, David did. Hell, he's building a harem of "things that should not be"™. It's the entire basis of the series, in fact.
Disguised in Drag: The Delta Green agent, in a particularly disturbing fashion.
Everybody's Dead, Dave: After Nancy is summoned and starts granting wishes, they start going really bad. One of them wanting to start a new Columbine shooting hallucinates one (only HE'S the one getting shot at, instead of doing the shooting) and when he gets killed, a lethal bullet wound appears in his head. One wishing that his brain was bigger (smarter) has his head swell to a fatally large size. One that wished for some killer sex...well, let's just say that she got what she wanted and leave it at that. Nancy then sacrifices the survivors to bind herself to this world and learn more about Dave's wish, leaving him as the only person left alive in the entire dorm.
Bonus points because, well...his name is Dave.
Evil Is Not a Toy: Unless all of the cultists had a death wish, summoning Nancy really didn't work out well for them. Some of them didn't even get a wish since Nancy sacrificed them so she could grant Dave's wish instead.
Genre Savvy: David, when it comes to dealing with real world-Lovecraft world interactions. Realizing that there must be a coverup agency, he goes into hiding for a few days to see how the agency operates (whether they use "arson" or "a gas leak" as an excuse for his roommates' murders) so he'll know if it's government-based or not.
Also "I knew I was not going to like that answer."
Gender Flip: Narla is of course one of the many Masks of the Crawling Chaos, although that's par for the course really. For those who didn't immediately catch it though, the Sleeper is none other than Tsathoggua.
Human Sacrifice: The cultists have a girl who's already had her arms severed. A bloody knife and Nancy actually appearing pretty much confirm that this went all the way.
Humans Are Special: According to the Mi-go. They're interested in us due to our ability to make leaps of logic, thinking of three without needing to think of two, as well as our incredible rate of development.
Idiosyncratic Episode Naming: Each chapter name is a reference to a Lovecraft story; e.g. "The Case Of David Andrew Bartlet", "The Transition Of Nancy Alhazred", etc.
Inspector Javert: Delta Green agents think David is an occult priest who murdered the whole cult to summon and bind Nancy. They refrain from taking direct action against him though, fearing Nancy's power.
Intercontinuity Crossover: Ow My Sanitydefinitely takes place in a version of the Delta Green universe with not only a cell of the aforementioned conspiracy investigating David and hints of Karotechia involvement, but the Third Book also brings in a Mi-Go complete with Grey masquerade.
Kick the Son of a Bitch: While Nancy killed the entire cult when summoned (well, those who didn't kill each other first), most of them had it coming, and it's implied some even wanted it to happen.
Knight in Sour Armor: Despite having a rather cynical world view, Dave often acts rather altruistically. According to the opening narration for chapter 3, it is quite possible to comprehend life's ultimate lack of meaning and still be perfectly satisfied with it.
Living Bodysuit: Inverted. The Delta Green agent wears a female Eldritch Abomination as a disguise, apparently in an attempt to assassinate David.
Logic Bomb: Dave makes a Mi-go faint with one of these.
Lovecraft Country: The comic seems to take place in one, unsurprisingly.
Debatable. People around Dave have a tendency to die horribly, and even in human form Nancy offers to kill people for him on occasion. The only "lite" part is the creatures' reactions to Dave, and he seems to be very special somehow.
Keep in mind The Dunwich Horror was also a Lovecraft story and the ending was far more optimistic than in most of his tales. It might not necessarily end with the death/insanity/transmorgrification of Dave and/or a bunch of other humans. Considering it's based on Delta Green the Earth is still fucked in the end, but Dave and friends might not be going mad, suicidal or primordial either.
Another example, The good ending ofEversionis just as lovecraftian as the bad one, if not more.
Besides, did he say WHO gets the Lovecraftian ending?
Mad Artist: Check out David's rough figure drawings of Nancy here and here.
Magnetic Girlfriend: Nancy. Of all the girls after David, there is only one whose proximity to David is not due to her presence: The Sleeper of N'Kai.
The Messiah: Despite his variousissues, David is astonishingly kind and generous to just about everyone, up to and including the many and varied Eldritch Abominations who want to do unutterably horrible things to him.
Which is probably why they have yet to do anything genuinely bad to him (at least directly or intentionally). In fact, one of these creatures basically offered to become his eternal bride and elevate him to godhood in return for his kindness. On the other hand, it may be that they see something special in him...the investigators certainly do.
Mistaken for Murderer: The paranormal investigators that deal with eldritch matters believe that David is an evil cult leader who sacrificed his followers to summon and bind an Eldritch Abomination into his service since he was the only survivor of Nancy's summoning. While his wish did get the remaining cultists killed and made Nancy his companion, David was just an ordinary(?) guy who was in the wrong place at the wrong (right?) time. His penchant for drawing Eldritch Abomination sketches just makes him look even more suspicious in their eyes.
Shout Out: A ridiculous number of them, many to H.P. Lovecraft and things related to his works.
The webcomic name itself is a shoutout to Ah! My Goddess. It's also a nod to Sanity being a statistic in the Call of Cthulhu RPG, which Delta Green is a campaign setting for.
Dave and Nancy's new house previously belonged to William Dyer.
Shubby being referred to as a "six-gun gorgon dynamo" by the two Elder Things (and their dialogue afterwards) comes from Six Gun Gorgon Dynamo by The Darkest of the Hillside Thickets...that is about Shub-Niggurath.
Just before Shubby's save, the Elder Things who wondered how Dave got into Phase Space mention how he reminds them of Randolph Carter.
The Stoic: David. His Brown Note reaction to the Eldritch Abominations he's seeing everywhere now is Dissociative disorder — i.e., he's going to be as stoic as he can be...until his insanity finally catches up with him.
Straight Man: The Mi-Go think like computers, and have no capacity for humor, or imagination. They make for the perfect straight man.
Unwanted Harem: The author has hinted at this. David seems to be accruing one made entirely of Eldritch Abominations. It's not really there yet, but some chapter names and Thaxton's deviant art gallery give us a peek at what's coming.
Wrong Genre Savvy: Not David but Delta Green thinks they're dealing with a Cult Leader that sacrificed his cult to bind a Eldritch Abomination. They're about half right.
Yandere: Word Of God has explicitly referred to the Sleeper of N'Kai as this. Then again, by Eldritch Abomination standards, it's a pretty good grasp on human ways...