Hello, dear Readers!

This is something I thought of in the middle of class, and I decided to write down my thoughts. It all started with looking at a bunch of random things on the internet during my free time, and I came across something along the lines of this:

"Hey, Aizawa, if you activated your quirk looking in the mirror, would you erase your own quirk?"

This thought intrigued me, and as I have recently taken an interest in Bungou Stray Dogs, and noticed the similarities and differences of Aizawa's and Dazai's powers, I wished to make a little fanfic analyzing the two with a simple question:

The Question: Would Aizawa be able to erase Dazai's ability if the two fandoms were in the same Universe and Abilities and Quirks were synonymous?

First, let's list some things we know about the two's Powers.

We'll start with Aizawa, whose quirk is called Erasure.

1. He can erase people's quirks by looking at them. As long as they are in his line of sight, he can erase their quirks, giving him quite a large range depending on terrain. His hair floats, and his eyes glow when the quirk is active.

2. The quirks are returned when he blinks or he looks away. It also won't go into effect if the target is concealed by something Aizawa can't see through.

3. It doesn't affect the body of mutation quirk users (as that is a permanent part of the person's body), but it can impede their quirk's use (i.e. Iida's engines wouldn't work despite them remaining on his legs, and Uraraka's finger pads would still be there; they'd just be ineffective.). Emitter and Transformation quirks are erased until he looks away or blinks.

4. It's not very good for long term combat due to the fact he has to refrain from blinking or looking away.

5. Erasure is an emitter quirk.

6. His Quirk gives him dry eyes as a side effect, limiting the time he can use it for.

To put it all together, Aizawa's quirk is an emitter quirk that erases other's quirks as long as they are in his line of sight and he refrains from blinking. His quirk allows for a greater range than Dazai's, but keeping his eyes open with the dry-eye drawback could cause him problems in long-term combat. His quirk is more suitable for ambushes rather than long fights out in the open (an example being USJ).

Now, let's take a look at Dazai's power: No Longer Human.

1. No Longer Human allows him to nullify any ability through skin contact.

2. He doesn't need to touch the person to nullify the ability. As long as the ability comes in contact with him, it will get nullified. (This is proven when he steps between Atsushi and Akutagawa, he touches Rashomon, but not Akutagawa). However, it's possible that to make sure the ability stays nullified for a desired amount of time, Dazai would have to come in contact with the user, then keep contact so the person can't activate their ability at all.

3. The ability is always active, so if an ability user touches him, their ability will be nullified.

4. Thus, if an ability is used on him, it won't affect him at all (proven during the Azure Messenger after switching places with Kunikida in the fight to disable the bomb).

5. It doesn't seem to have adverse side effects beyond the fact he can't turn it off and must be careful with being touchy-feely.

6. As his ability relies on contact, there are only so many abilities he can nullify at a time (with only two hands and all those bandages).

To sum up Dazai's ability, it basically makes him immune to abilities that come into contact with him. However, as he needs to come in contact with the person to disable the ability for longer periods of time (like when fighting with a partner that needs time to power a move or something along those lines), that means he needs to get close, and puts himself in danger of getting hit by weapons like guns and knives.

The main similarities between the quirks and abilities:

1. Both allow the user to erase another's quirk/ability temporarily.

2. Both rely on a sense that is hard to maintain constantly in battle, especially against many opponents (eyesight and touch).

Summing things up/Doing Some Analysis:

Let's look at each side's argument, for this has the potential to go either way.

If Dazai is not effected by Erasure:

Aizawa's powers erase the quirk of all in his line of sight, and Dazai's power makes him immune to abilities that are used on him. These powers cancel each other out, but as "emitter" type abilities also don't affect Dazai, it is possible that Dazai would be unaffected by the erasure quirk. As his ability is always active, it should cancel out the quirk before it takes effect.

If Dazai is affected by Erasure:

Erasure is able to erase the skills behind mutation quirks, even if his quirk doesn't change the physical body, and as Dazai's ability is always active and basically changes his body for his ability, it could be seen as a mutation type. Thus, he would be affected like other mutation quirks: his body wouldn't change, but he would lose the effects that come with his mutation.

As a bonus, how Dazai's ability would affect Aizawa:

As Aizawa's quirk relies on his line of sight, even if Dazai was vulnerable to the hero's quirk, he would simply have to get out of that line of sight and make contact with Aizawa to nullify Erasure. As Dazai would still be able to nullify the quirk because Aizawa isn't "immune" to quirks/abilities like Dazai is, Aizawa is vulnerable to Dazai's ability regardless of whether or not Dazai is affected by Aizawa's quirk. Once Dazai nullifies Erasure, it is simply a matter of maintaining contact, leaving the fight to physical ability.

Well, this was an interesting analysis. It's not very long, and I could have left out some stuff, so if you have something to add, leave it in the reviews or PM me about it, and we can discuss it! I'm considering making this multiple chapters, each one doing a new analysis. Tell me what you think, for I believe this has the potential to be fun and interesting!