diff --git a/apps/tests/phase104_read_digits_json_cur_min.hako b/apps/tests/phase104_read_digits_json_cur_min.hako
new file mode 100644
index 00000000..84713f14
--- /dev/null
+++ b/apps/tests/phase104_read_digits_json_cur_min.hako
@@ -0,0 +1,25 @@
+// Phase 104 (P2): real-app derived fixture from apps/libs/json_cur.hako:read_digits_from
+// Expect numeric output lines: 2 then 1
+
+static box Main {
+  read_digits_from(s, pos) {
+    local out = ""
+    local i = pos
+    if i < 0 { return out }
+
+    loop (true) {
+      local ch = s.substring(i, i+1)
+      if ch == "" { break }
+      if ch == "0" || ch == "1" || ch == "2" || ch == "3" || ch == "4" || ch == "5" || ch == "6" || ch == "7" || ch == "8" || ch == "9" { out = out + ch  i = i + 1 } else { break }
+    }
+    return out
+  }
+
+  main() {
+    local a = read_digits_from("12x", 0)
+    local b = read_digits_from("9", 0)
+    print(a.length())
+    print(b.length())
+    return "OK"
+  }
+}
diff --git a/docs/development/current/main/phases/phase-104/README.md b/docs/development/current/main/phases/phase-104/README.md
index bc13368d..f4043d2e 100644
--- a/docs/development/current/main/phases/phase-104/README.md
+++ b/docs/development/current/main/phases/phase-104/README.md
@@ -5,5 +5,9 @@ Fixture: `apps/tests/phase104_read_digits_loop_true_min.hako`（expected: `2`, `
 Smokes: `tools/smokes/v2/profiles/integration/apps/phase104_read_digits_vm.sh` / `tools/smokes/v2/profiles/integration/apps/phase104_read_digits_llvm_exe.sh`
 
 DONE:
-- loop(true) counter 抽出: `LoopTrueCounterExtractorBox`
+- loop(true) counter 抽出（契約SSOT+Fail-Fast）: `LoopTrueCounterExtractorBox`
 - break 条件（break when true）正規化 + digit set 固定: `ReadDigitsBreakConditionBox`
+
+P2（実ループ由来の回帰面増強）:
+- Fixture: `apps/tests/phase104_read_digits_json_cur_min.hako`（json_cur.hako 由来, expected: `2`, `1`）
+- Smokes: `tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_vm.sh` / `tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_llvm_exe.sh`
diff --git a/tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_llvm_exe.sh b/tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_llvm_exe.sh
new file mode 100644
index 00000000..834437eb
--- /dev/null
+++ b/tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_llvm_exe.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+# Phase 104: read_digits(loop(true)) real-app derived (LLVM EXE parity)
+
+source "$(dirname "$0")/../../../lib/test_runner.sh"
+source "$(dirname "$0")/../../../lib/llvm_exe_runner.sh"
+export SMOKES_USE_PYVM=0
+require_env || exit 2
+
+llvm_exe_preflight_or_skip || exit 0
+
+# Phase 97/98/100 SSOT: plugin dlopen check → build only if needed → dlopen recheck.
+FILEBOX_SO="$NYASH_ROOT/plugins/nyash-filebox-plugin/libnyash_filebox_plugin.so"
+MAPBOX_SO="$NYASH_ROOT/plugins/nyash-map-plugin/libnyash_map_plugin.so"
+STRINGBOX_SO="$NYASH_ROOT/plugins/nyash-string-plugin/libnyash_string_plugin.so"
+CONSOLEBOX_SO="$NYASH_ROOT/plugins/nyash-console-plugin/libnyash_console_plugin.so"
+INTEGERBOX_SO="$NYASH_ROOT/plugins/nyash-integer-plugin/libnyash_integer_plugin.so"
+
+LLVM_REQUIRED_PLUGINS=(
+  "FileBox|$FILEBOX_SO|nyash-filebox-plugin"
+  "MapBox|$MAPBOX_SO|nyash-map-plugin"
+  "StringBox|$STRINGBOX_SO|nyash-string-plugin"
+  "ConsoleBox|$CONSOLEBOX_SO|nyash-console-plugin"
+  "IntegerBox|$INTEGERBOX_SO|nyash-integer-plugin"
+)
+LLVM_PLUGIN_BUILD_LOG="/tmp/phase104_read_digits_json_cur_plugin_build.log"
+llvm_exe_ensure_plugins_or_fail || exit 1
+
+INPUT_HAKO="$NYASH_ROOT/apps/tests/phase104_read_digits_json_cur_min.hako"
+OUTPUT_EXE="$NYASH_ROOT/tmp/phase104_read_digits_json_cur_llvm_exe"
+
+EXPECTED=$'2\n1'
+EXPECTED_LINES=2
+LLVM_BUILD_LOG="/tmp/phase104_read_digits_json_cur_build.log"
+if llvm_exe_build_and_run_numeric_smoke; then
+  test_pass "phase104_read_digits_json_cur_llvm_exe: output matches expected (2, 1)"
+else
+  exit 1
+fi
diff --git a/tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_vm.sh b/tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_vm.sh
new file mode 100644
index 00000000..bed8931a
--- /dev/null
+++ b/tools/smokes/v2/profiles/integration/apps/phase104_read_digits_json_cur_vm.sh
@@ -0,0 +1,55 @@
+#!/bin/bash
+# Phase 104: read_digits(loop(true)) real-app derived (VM)
+
+source "$(dirname "$0")/../../../lib/test_runner.sh"
+export SMOKES_USE_PYVM=0
+require_env || exit 2
+
+PASS_COUNT=0
+FAIL_COUNT=0
+RUN_TIMEOUT_SECS=${RUN_TIMEOUT_SECS:-10}
+
+INPUT="$NYASH_ROOT/apps/tests/phase104_read_digits_json_cur_min.hako"
+
+echo "[INFO] Phase 104: read_digits(loop(true)) json_cur derived (VM) - $INPUT"
+
+set +e
+OUTPUT=$(timeout "$RUN_TIMEOUT_SECS" env \
+  NYASH_DISABLE_PLUGINS=0 \
+  HAKO_JOINIR_STRICT=1 \
+  "$NYASH_BIN" --backend vm "$INPUT" 2>&1)
+EXIT_CODE=$?
+set -e
+
+if [ "$EXIT_CODE" -eq 124 ]; then
+  echo "[FAIL] hakorune timed out (>${RUN_TIMEOUT_SECS}s)"
+  FAIL_COUNT=$((FAIL_COUNT + 1))
+elif [ "$EXIT_CODE" -eq 0 ]; then
+  EXPECTED=$'2\n1'
+  CLEAN=$(printf "%s\n" "$OUTPUT" | grep -E '^-?[0-9]+$' | head -n 2 | paste -sd '\n' - | tr -d '\r')
+  if [ "$CLEAN" = "$EXPECTED" ]; then
+    echo "[PASS] Output verified: 2 then 1"
+    PASS_COUNT=$((PASS_COUNT + 1))
+  else
+    echo "[FAIL] Unexpected output (expected lines: 2 then 1)"
+    echo "[INFO] output (tail):"
+    echo "$OUTPUT" | tail -n 60 || true
+    FAIL_COUNT=$((FAIL_COUNT + 1))
+  fi
+else
+  echo "[FAIL] hakorune failed with exit code $EXIT_CODE"
+  echo "[INFO] output (tail):"
+  echo "$OUTPUT" | tail -n 60 || true
+  FAIL_COUNT=$((FAIL_COUNT + 1))
+fi
+
+echo "[INFO] PASS: $PASS_COUNT, FAIL: $FAIL_COUNT"
+
+if [ "$FAIL_COUNT" -eq 0 ]; then
+  test_pass "phase104_read_digits_json_cur_vm: All tests passed"
+  exit 0
+else
+  test_fail "phase104_read_digits_json_cur_vm: $FAIL_COUNT test(s) failed"
+  exit 1
+fi
+