Back in 2013, Google image search was very powerful we could reverse search everything that was photoshopped, trased or cropped to reach to the original source.
Like this https://e-hentai.org/g/610127/9377294bb3/ (see the comment section below)
But then they decided to nerf it into the ground. There are some alternative services such as IQDB but they are nowhere near as good as google image search in prime I still really missed it.

Edit: ok, i tried (for science). turns out that was not that bad. the technology was weakened, yet still there.
#2-9 https://e-hentai.org/s/1bc3447336/811713-105 [HERENCIA] Relaxation Yuka En
#10-20 https://e-hentai.org/s/39df92a29f/1092734-1699 [CLOCKUP] Kenzen! Hentai Seikatsu no Susume
#21-28 https://e-hentai.org/s/7935fbc220/724946-127 [Orcsoft] Kanojo wa Dare to demo Sex suru
#29-36 https://e-hentai.org/s/19af8a30c5/640324-783 [Tsurumiku] Yume Kui
#37-54 https://e-hentai.org/s/4448d976ce/927137-188 [Pin-Point] Tsuiraku Jinsei
#55-65 https://gelbooru.com/index.php?page=post&s=view&id=3322964 [Lilith] Taimanin Asagi Battle Arena
#66-73 https://e-hentai.org/s/7a37a9b695/1000443-416 [SILKY'S SAKURA] Mama no Oppai
#74-94 https://e-hentai.org/s/170fcd23dc/709358-79 [Pin-Point] Inshitsu Otaku ni Ikareru Imouto
#101-110 https://e-hentai.org/s/6fd8a93169/1067427-26 [ANIM.teamMM] Tsuma no Nikuana ni Homestay Suru Macho Ryuugakusei
#111-120 https://e-hentai.org/s/82a6558364/1067427-477 [ANIM.teamMM] Tsuma no Nikuana ni Homestay Suru Macho Ryuugakusei
#121-128 https://e-hentai.org/s/9915630350/900206-509 [ALICESOFT] Tsumamigui 3
#129-138,153-161 https://e-hentai.org/s/83a78dce6a/1092739-55 [Studio Ubai] Psy-min Appli
#145-152 https://e-hentai.org/s/a43bb45e67/722241-1097 [Clock Up] Fraternite
#162-169 https://e-hentai.org/s/a638fcc111/972506-63 [PakoPako Soft] Pako ★ Shisu
#170-178 https://e-hentai.org/s/7bc1be0269/984732-80 [HERENCIA] Relaxation Yuka M
#179-184 https://e-hentai.org/s/60ddc7883b/984732-23 [HERENCIA] Relaxation Yuka M
#185-193 https://e-hentai.org/s/54ece5165f/724946-185 [Orcsoft] Kanojo wa Dare to demo Sex suru
#194-208 https://e-hentai.org/s/577510773c/1024149-101 [ALICESOFT] Heartful Maman
#209-226 https://e-hentai.org/s/11e627de3e/1092734-1039 [CLOCKUP] Kenzen! Hentai Seikatsu no Susume
#236-244 https://e-hentai.org/s/7c29cebf02/929250-132 [Studio Charen] Houkago Saimin Club 3
#245-253 https://e-hentai.org/s/d59105c5e4/935278-248 [Atelier Sakura] Kashidashi Tsuma, Marina no Netorase Houkoku Gaiden 1
#256 https://e-hentai.org/s/3cd2b2c05c/974001-139 [Bishop] Mesu Kyoushi 4
#257 https://e-hentai.org/s/df1b91be27/974001-1214 [Bishop] Mesu Kyoushi 4

Last edited on 22 September 2017, 16:58.

Base +11, jinkjink -6, xz8885 +6, TheOldDeus +6, Mrsuperhappy +29, zexalarcv123 +4, Laharl_EAC +10, yuuuuuuoi +6, jeeyi12 +6, plaquebringer +6, Refyrsen +6, illusioninusall +15, ROBERTO2109 +6, and 17 more...

只有沙希才是纯爱

Base +5, zexalarcv123 +4, MG1937 +3, 國王男孩 +5, a912654473 +6, clear in the mist +5, TNTYOO +6

支持！~

Base +6, nsholic +6, AndroidTierra +6

拿别的图p个脑袋上去……何必呢

Base +8, rex31 -5, abcd98328 +5, xz8885 +6, tom19970526 +3, err-404 -1, yzw1635994342 +2, Alex_viktor +4, DDDD11a -5, yjj163419 +3, REcount -20, kaname_madoka -7, Wuke. +5, and 8 more...

for science! you've done we'll pal

Base +6, zexalarcv123 +4, plaquebringer +6, Ceon +6, Refyrsen +6, ROBERTO2109 +6, AwesomeArk +5

真是满满的爱

Base +6, zexalarcv123 +4

这种玩意真有人看?给半星都嫌多

Base +6, nsholic -6, a912654473 -6, Lmx1999 -6, ysbwbwyshs -5, Wuke. +5, gvdtybcd -2, t_shitman -21, swordonly -6, 周子恒 -6, ljk2000216 -6, Qiu Shiyu -2

P图的功力确实可以。献媚的雪乃杀伤力真的很强

Base +6, clear in the mist +4

说实话，不喜欢，人物比例不协调，实在看不下去。。。

Base +2

Redrawers and image sourcers are doing God's work. Bless.

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