This will provide simple steps for getting this achievement.
So you want to show the world of Revachol your honour? This guide will allow you to build a colossal arch of honour for all to witness (Note Spoilers, not recommended to read this before you've finished the game). At time of writing, 0 percent of players have this achievement, and it's a bit quirky so I've decided to help out in the name of all that is disco.
However, the way to get maximum honour is not necessarily straightforward. In order to be honourable, you sometimes have to commit acts that seem immoral and then make good, or follow instructions blindly without question. A truly honourable man succumbs to temptation in order to overcome it. Honour is not the same as morality, it has its own weird logic as you will see in the guide.
Tip: Keep especially close watch for dialogue options that mention honour, as they should invariably give you an honour point.
In order to achieve these steps, I created a 3/5/2/2 character with Authority as his primary skill. Authority tends to chime in when your actions will be honourable or dishonourable. Esprit de Corps is a secondary skill. Otherwise, I recommend putting some points in Shivers and Perception, and other skills as needed to unlock white checks if you fail them. Some key additions in the THC were Caustic Echo, Col do Ma Qua Qua, Spotlight something, and Apricot-Scented One. Basically, all of the thoughts that provide Perception with minimal drawback, as it is one of the essential skills in the game. Once you hit 5 honour, you can get Overactive Honour Gland, which you might as well in keeping with hunting this achievement
This will provide an outline of actions that you can take to accrue honour points.
Investigating the corpse
Try to pull the boots off, and when Kim reprimands you, agree with him and do not take the boots. Make note of everything you have found in the autopsy report. 1(+1)
Interacting with Joyce
Accept the 130 real to pay off your debt. You have 2 opportunities to gain honour. You get 1 for refusing to ask for any more money, and 1 for saying that you are "an honourable policeman" who will not be swayed by her donation.
I am sure there is a dialogue that comes up later where you can choose a line that says something like "on my honour", but I didn't note down which one. 4(+3)
Ask Manana for money
When he throws you a 1 real piece, leave it on the ground. 5(+1)
Sleeping dockworker in the hostel
If you have at least 5 interfacing you can swipe the sleeping docker's pass. Show it to Manana and admit that you took it and return it. 6(+1)
Wheelchair lady in hostel
Ask if sweeties get money, and when she offers you a pin give it back to her (not tested but suspect this works).
When asking her about cryptids, agree to ask about just one and then stop speaking to her. 7 (+1)
Interacting with Evart
When you are asked to open the "weasel's door", just open it and go straight back to Evart. DO NOT GO INSIDE and let him know you didn't. You can accept his check for 25 real, but when he offers you a 5 real note, to be on the safe side refuse it.
When you are asked to get the signatures, do as he asks and get the signatures without forging them. 9 (+2)
"Sunday Friend" in Apt 20
Turn Klaasje over to him and pick the honour dialogue option. 10 (+1)
Washerwoman in village
Refuse her offer of a place to sleep the first time. You can accept afterwards, but refusing saying it is unbecoming of an RCM officer gets you a point.
Titus must survive the showdown. This will require you intervening and shooting the guy in the face. Pass the easier checks to get him off-guard then go for the kill. Speak to Titus after you recover and say it was an honour to fight with him 11 (+1)
When speaking to the Deserter, pick the honour dialogue option in reference to his refusal to surrender. 12 (+1).