My favorite pens and pencils that I can recommend:
This list is constantly updated as I discover new tools and change my habits. Also, some of the products that were listed here are sadly no longer available – I will try to update this list for this, too!
IndiGraph fountain pen, EF nib
I have been using this fountain pen since I got the prototype from its creator just for some testing. It stayed in my pen case, and I’m still using the final version with the extra fine EF nib. This fountain pen (thanks to a specially designed cap) can be safely used with black, waterproof India Ink, which makes it perfect for sketching and using together with watercolors. The pen is almost entirely made of metal, and the nibs are very easy to replace. I have been making all my recent storefronts illustrations with this fountain pen.

Pilot ELABO (or Falcon outside of Japan), metal body, SF nib.
I have been interested in this pen for some time as I have seen excellent art done with it by many artists. I finally bought the metal body, SF nib version, and it has never left my pen case so far. I can not explain it very clearly, but there is a special something about how the more flexible nib allows for very thin and controlled lines and more dynamic strokes too. A very unique pen, but not for everyone, I expect. I drew the lines for, for example, this piece with this fountain pen. Tip: there are plastic and metal versions – they feel a bit different in hand due to weight difference.

ROTRING ISOGRAPH
I usually use my fountain pens for line work, but if I want thinner, more stable lines, I use an isograph. I used to use a Faber-Castell rapidograph, but as they are not easily available in Japan, I’m currently using the Rotring Isograph pens of various line widths. I usually take good care of cleaning the pens if I don’t plan to use them for longer, so I haven’t had any problems with clogging. I’m using the original Rotring black ink. One tip: The line thickness and flow can vary depending on how well the paper handles the Rotring ink.

Inks:

De Atramentis Document ink Black and Grey
Good, very waterproof fountain pen inks. I use them both in regular fountain pens, not meant for India Ink. I especially like how the grey ink allows me to get a bit of a depth effect, with lines not being perfectly black.

PILOT SEIZUYO (drafting ink)
This is the standard ink used with dip pens by most Japanese comic artists. As I’m not very comfortable with drawing only using nib pens, I mostly use this ink with brushes for covering larger areas black or for adding textures and dry-brush effects to my illustrations (like HERE). This ink also smells nice (?).

Platinum – Carbon ink
I use this black ink a lot in my works when waterproof black ink is needed. This ink gives beautiful black lines and washes and is very waterproof. I use it in fountain pens while being very careful to clean them afterward and not let them dry out!

ROTRING black ink
For the isograph pens, I use the original Rotring black ink. This ink is beautifully black and fully waterproof. It also dries really fast on paper, so I did not have problems smudging it with my hand by accident. One tip: the white ink of the same brand comes in a similar package, and I once bought it by mistake!
Pencils
Mitsu-Bishi Hi-Uni from grade F to 5B
I tried a lot of Japanese brand pencils and like all of them, but for me, the Hi-Unis are the best (closely followed by TOMBOW). These pencils feel extremely soft and “silky” and give consistent, dark lines. Also, the quality of the wood and finishing is superb! Because of these characteristics, these pencils are widely used in Japanese animation for drawing animation frames. Tip: Japanese pencils generally feel a lot softer than European pencils of the same hardness.

Erasers

Mijello portable set.
I wanted to keep the number of watercolor sets I have to a minimum, so I actually use them.
The above main box is meant to be used in the studio only, so I have this smaller one that can be used both at my desk and (if necessary) to do some sketching outside. This surprisingly sturdy and compact box is a 16 color Holbein palette. It can be expanded, however, to hold 24 or even 25 half-pans if you fill in the middle row too.
It’s a perfect match for the Mijello Mission Gold Pure Pigments set I have, that consists of 25 colors if you ignore the white. The Pure Pigments paints are all single pigment colors and provide excellent saturation, which is useful when painting simple sketches. Because of that, I have been using the Mijello paints more and more recently as I’m aiming for a more loose style in my paintings. I quite enjoy painting with them, and I did not have any problems – except them being runnier than Schmincke or Holbein, so you have to be careful about how you store your palettes.
Brushes:
Escoda Perla SINTETICO sizes 2 to 8
These are the main, everyday use brushes for most of my watercolor painting. These are made of great quality synthetic fibers, which are springy but not too stiff and can hold (and release) water well enough that I don’t feel that I’m missing anything compared to natural hair brushes. This series of brushes also have a bit thicker handles than other brands, which I like a lot. The minus is that the white tips get dyed dirty blue when used – it does not impact the usability – only looks.
Raphael travel collapsible brush
A collapsible, synthetical hair brush great for traveling and outdoor sketching, but I find that I also use it a lot at my desk. It has a long tip, but at the same time, it’s more round shaped than my other brushes – perfect for all these rougher, more sketch-like paintings.
Paper

HOLBEIN Waterford white cold and hot press
This 300g/m heavyweight watercolor paper is one of the best I used, with a good quality-to-price ratio. It’s thick, so it does not warp very much with my style of watercolor painting (I don’t use so much water). It also has a rather unyielding surface, so it handles sketching with a hard pencil, intensive erasing, and ink very nicely (the ink does not seep in, bleed or spread uncontrollably). At the same time, it’s a pleasure to use watercolor on this paper as it gives smooth transitions and really flat, even washes with beautiful, not obnoxious, texture. I used to use the cold-pressed variation most of the time, but recently I’m growing more and more fond of the hot-press one, which has almost no texture. It’s perfect for watercolor and fountain pen art.
